U.S. patent application number 14/000510 was filed with the patent office on 2014-01-16 for shoe for practicing sports involving gliding over the snow or for walking.
This patent application is currently assigned to SALOMON S.A.S.. The applicant listed for this patent is Franck Constant, Pierre Gignoux, Thomas Saillet. Invention is credited to Franck Constant, Pierre Gignoux, Thomas Saillet.
Application Number | 20140013630 14/000510 |
Document ID | / |
Family ID | 44269235 |
Filed Date | 2014-01-16 |
United States Patent
Application |
20140013630 |
Kind Code |
A1 |
Gignoux; Pierre ; et
al. |
January 16, 2014 |
SHOE FOR PRACTICING SPORTS INVOLVING GLIDING OVER THE SNOW OR FOR
WALKING
Abstract
Boot (1) intended for the practice of sports involving gliding
on snow or walking, characterized in that it includes an outer
shell (2, 2', 20, 26, 26', 34, 42) made of a rigid material, the
shell (2, 2', 20, 26, 26', 34, 42) including a rear cradle (22, 28,
28', 39, 44) provided to hold the heel of the user, the rear cradle
(22, 28, 28', 39, 44) being extended forward by a blade-shaped
portion (6) defining a bending zone, the rear cradle (22, 28, 28',
39, 44) comprising a peripheral wall (5, 31) and a bottom, the
bottom of the cradle and the blade-shaped portion partially
defining the sole assembly of the boot, and characterized in that
it includes an inner liner (20).
Inventors: |
Gignoux; Pierre;
(Saint-Martin d'Uriage, FR) ; Constant; Franck;
(Albens, FR) ; Saillet; Thomas; (Chainaz Les
Frasses, FR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Gignoux; Pierre
Constant; Franck
Saillet; Thomas |
Saint-Martin d'Uriage
Albens
Chainaz Les Frasses |
|
FR
FR
FR |
|
|
Assignee: |
SALOMON S.A.S.
Metz-Tessy
FR
|
Family ID: |
44269235 |
Appl. No.: |
14/000510 |
Filed: |
February 20, 2012 |
PCT Filed: |
February 20, 2012 |
PCT NO: |
PCT/FR12/00065 |
371 Date: |
September 23, 2013 |
Current U.S.
Class: |
36/117.1 |
Current CPC
Class: |
A43B 5/0421 20130101;
A43B 5/0496 20130101; A43B 13/12 20130101; A43B 5/0482 20130101;
A43B 5/049 20130101; A43B 13/026 20130101; A43B 1/0018 20130101;
A43B 13/16 20130101; A43B 5/04 20130101; A43B 1/00 20130101; A43B
3/0052 20130101; A43B 5/0411 20130101; A43B 5/0472 20130101 |
Class at
Publication: |
36/117.1 |
International
Class: |
A43B 5/04 20060101
A43B005/04 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 21, 2011 |
FR |
1100509 |
Claims
1. Boot (1), particularly intended for the practice of sports
involving gliding on snow or walking, characterized in that it
includes an outer shell (2, 2', 20, 26, 26', 34, 42) made of a
rigid material, the shell (2, 2', 20, 26, 26', 34, 42) including a
rear cradle (22, 28, 28', 39, 44) provided to hold the heel of the
user, the rear cradle (22, 28, 28', 39, 44) being extended forward
by a blade-shaped portion (6) defining a bending zone, the rear
cradle (22, 28, 28', 39, 44) comprising a peripheral wall (5, 31)
and a bottom, the bottom of the cradle and the blade-shaped portion
partially defining the sole assembly of the boot, and characterized
in that it includes an inner liner (20).
2. Boot (1) according to claim 1, characterized in that the shell
(2, 2', 20, 26, 26', 34, 42) includes a front cradle (21, 27, 27',
38, 45, 47), the blade-shaped portion connecting the rear cradle to
the front cradle, the blade-shaped portion extending in the area of
the metatarsus of a user.
3. Boot (1) according to claim 1, characterized in that the rear
cradle and the blade-shaped portion are unitary elements.
4. Boot (1) according to claim 1, characterized in that the rear
cradle and the blade-shaped portion are separate elements.
5. Boot (1) according claim 1, characterized in that the thickness
of the peripheral wall (5) of the rear cradle is less than 1.5
millimeters.
6. Boot (1) according to claim 1, characterized in that it includes
a front cradle, and in that the thickness of the peripheral wall of
the front cradle is less than 1.5 millimeters.
7. Boot according to claim 1, characterized in that the thickness
(ep) of the blade-shaped portion (6) in the bending zone (Z) is
less than 4.0 millimeters.
8. Boot according to claim 1, characterized in that the thickness
(ep) of the peripheral wall (5) tapers off between the bottom (6)
and the upper opening (7).
9. Boot according to claim 1, characterized in that the minimum
width of the bending zone (Z) is at least greater than 5.0
millimeters.
10. Boot according to claim 9, characterized in that the minimum
width of the bending zone (Z) is between 20 and 30 millimeters, and
is preferably on the order of 25 millimeters.
11. Boot according to claim 1, characterized in that the shell is
entirely made of composite materials, and in that the thickness
(ep) of the peripheral wall (5) is between 0.5 and 1.2
millimeters.
12. Boot according to claim 11, characterized in that it is made
entirely of carbon fibers, and in that the thickness (ep) of the
peripheral wall (5) is between 0.5 and 0.8 millimeters.
13. Boot according to claim 11, characterized in that at least the
peripheral wall (5) is made of glass fibers, and in that the
thickness (ep) of said peripheral wall (5) is between 0.8 and 1.2
millimeters.
14. Boot according to claim 1, characterized in that the
blade-shaped portion (6) is made of composite materials, and in
that it includes unidirectional fibers of the composite material in
the bending zone (Z).
15. Boot according to claim 1, characterized in that the bending
zone (Z) defines a front cradle and a rear cradle, the materials of
the front and rear cradles being different from one another, the
blade-shaped portion (6) being made of carbon fibers.
16. Boot according to claim 1, characterized in that lightening
holes are provided in the rear cradle.
17. Boot according to claim 1, taken together with claim 16,
characterized in that at least the cradle is made of a plastic
material, and in that the thickness (ep) of the cradle is less than
or equal to 1.5 millimeters.
18. Boot (1) according claim 1, characterized in that the bending
zone (Z) defines a front cradle and a rear cradle, the shell
comprising the front cradle and the rear cradle, the shell
comprising a means for fixing the front and rear cradles in the
area of overlap of the front and rear bottoms of the cradles.
19. Boot (1) according to claim 1, characterized in that the bottom
of the rear cradle extends beneath the bottom of the front cradle,
the fixing means being arranged beneath the front cradle.
20. Boot (1) according to claim 1, characterized in that the front
bottom extends beneath the rear bottom, the fixing means being
arranged beneath the rear cradle.
21. Boot according to claim 18, characterized in that the fixing
means (33, 33') is removable.
22. Boot according to claim 1, characterized in that the shell is a
unitary element.
23. Boot according to claim 1, characterized in that the shell
comprises a stiffening blade (35) extending at least beneath the
bending zone (Z), said stiffening blade (35) being adapted to
assume an active position in which said stiffening blade (35)
thickens the sole assembly in the bending zone (Z), and an inactive
position in which the end (37) of the stiffening blade (35) is
free.
24. Boot according to claim 23, characterized in that the free end
(37) of the stiffening blade (35) extends rearward of the bending
zone (Z).
25. Boot according to claim 24, characterized in that the free end
(37) of the stiffening blade (35) is adapted to be retained in the
active position by a removable retaining means (40).
26. Boot according to claim 1, characterized in that it comprises
protective upright panels (12) in the area of the malleoli.
27. Boot according to claim 1, characterized in that the bending
zone (Z) defines a front cradle and a rear cradle, and in that the
front cradle has a central upper recess (8).
28. Boot according to claim 1, characterized in that the shell
comprises through holes adapted to receive fixing screws (11), and
in that it comprises inner shoulders arranged around the through
holes, adapted to house the heads of said fixing screws (11).
29. Boot according to claim 1, characterized in that the bending
zone (Z) defines a front cradle and a rear cradle in the shell
(42), and in that the boot comprises two straight stays (43)
connecting the walls of the rear cradle (44) to the walls of the
front cradle (45), respectively.
30. Ski boot according to claim 1, characterized in that the
bending zone (Z) defines a front cradle and a rear cradle in the
shell (42'), and in that the boot comprises a Y-shaped stay (46)
connecting the walls of the rear cradle (44) to the front cradle
(47).
Description
[0001] The invention relates to a shoe adapted to the practice of
sports involving gliding on snow, or walking. The invention relates
more particularly to a boot suitable for the practice of Nordic
skiing, such as cross-country skiing or ski touring, mountaineering
skiing, ski mountaineering or telemark, that is to say, a practice
for which a user alternately lifts the heel. The invention also
relates to a boot adapted to the practice of mountain walking or
mountaineering. The invention also relates to a shell for a sports
shoe.
[0002] The practice of these activities, or of an activity such as
cross-country skiing requires the use of boots that are relatively
torsionally rigid, between the front and rear of the boot, in order
to accurately transmit the foot actions to the ski, while retaining
the bending flexibility necessary for the foot rolling movement in
the area of the metatarsal joint.
[0003] With respect to cross country skiing itself, the
aforementioned relative rigidity was lacking in the early cross
country ski boots when the so-called "skating step" technique was
first introduced. However, a technical solution has been found,
involving the use of reinforcements generally made of composite
materials, which are superimposed and connected to the existing
structure made of synthetic and/or thermoplastic materials. Indeed,
the cross-country ski boot conventionally have an assembled
construction, in which the boot includes a flexible upper mounted
on a lasting board, the assembly being glued onto an outer sole,
and the reinforcing elements generally being attached to the
outside of the upper, to complement the conventionally used
reinforcements and stiffeners.
[0004] The boots thus produced are more rigid, thereby allowing for
better control of the ski and balance; but they have also become
heavier, as the additional reinforcements add to the weight of the
boot, even if they are made of the lightest possible materials.
[0005] More generally speaking, the boots according to the prior
art have an upper and a sole assembly with quite complex
structures, for a high weight. The complexity is due to the
multitude of components required to manufacture the upper, on the
one hand, and the sole assembly, on the other hand. The upper
includes at least a first envelope providing the general appearance
of the boot, a stiffener for supporting the heel, localized
reinforcements added to the first envelope to obtain localized
increases in mechanical strength; as well as a second envelope or
liner, housed in the first envelope, to perform one or more
functions such as providing comfort, thermal insulation, or the
like. The sole assembly includes at least a first lasting board,
adapted to hold the constituent elements of the upper together. The
sole assembly further includes an outsole, adapted to contact the
ground, as well as an insole, housed in the envelopes. It should be
noted in passing that the outsole often includes two or more
layers, including a wear layer and a damping layer.
[0006] Still with respect to boots according to the prior art, the
complexity of the structure renders the manufacturing complex.
Indeed, it is necessary to group the constituent elements of the
upper together, by applying them onto a blank, and then by holding
them, generally using an adhesive, on the lasting board. The
subassembly thus made then receives the outsole and the insole.
Thus, the manufacture is quite complex and, ultimately, given the
number of components, the resulting boot is quite heavy.
[0007] Furthermore, a more or less substantial flexural rigidity is
sometimes necessary in the cross-country, alpine, or mountaineering
ski boot. There is currently no response to this constraint, and
the only solution is to have a plurality of boots, depending upon
the practice. In cross-country skiing, for example, it is necessary
to have a pair of flexurally flexible boots to practice the
so-called classic technique, and a pair of flexurally rigid boots
to practice the skating step technique. This can be particularly
difficult in competitions combining two events, such as a classic
event immediately followed by a skating step event without
interrupting the timer. The boots used for these types of events
are hybrid boots in which rigidity is intermediate between the two
types of boots. Therefore, this compromise is not ideal for neither
of these two skiing techniques.
[0008] Broadly speaking, the invention provides a boot, adapted to
the practice of a sport involving gliding on snow or walking, as
mentioned above, which concurrently has good torsional rigidity,
good flexural flexibility, and reduced weight. Thus, the invention
seeks to reduce user fatigue, or to help improve user
performance.
[0009] One of the objects of the present invention is therefore to
overcome the drawbacks of the prior art by providing a Nordic ski
boot having with good torsional rigidity, good flexural
flexibility, and reduced weight, while meeting comfort
requirements.
[0010] An object of the invention is also to provide an adaptable
boot, whose rigidity is adjustable depending upon the practice.
[0011] To this end, the invention provides a boot adapted to the
practice of sports involving gliding on snow or walking. The boot
according to the invention is characterized in that it includes an
outer shell made of a rigid material, the shell including a rear
cradle adapted to hold the heel of the user, the rear cradle being
extended forward by a blade-shaped portion defining a bending zone,
the rear cradle comprising a peripheral wall and a bottom, the
bottom of the cradle and the blade-shaped portion partially
defining the sole assembly of the boot, and characterized in that
it includes an inner liner.
[0012] The shell includes the rear cradle and the blade-shaped
portion and, consequently, the boot has good torsional rigidity and
good flexural flexibility. The liner arranged in the shell provides
the boot with a minimum of use comfort. It can be said that the
invention separates the elements of the boot depending on their
intended function, that is to say, either a function of
transmission of sensory information or of transmission of steering
impulses, by the torsional rigidity or the flexural flexibility of
the shell, or a function of providing comfort, retention and/or
envelopment for the foot, by arranging the liner in the shell. The
separation of the elements of the boot simplifies the structure
thereof, compared to a boot with integrated upper according to the
prior art. The separation of the elements also makes it possible to
optimize the structure or function thereof. In the invention, by
placing a single material where necessary, and thus by avoiding
duplicative layer overlays, the boot obtained includes a reduced
number of parts. The separation of functions makes it possible to
optimize each element, in particular the reinforcing element, and
thus to minimize the weight. This means that the structure created
by the invention lightens the boot. A resulting technical effect is
a reduction in its mechanical inertia, compared to a boot according
to the prior art. To summarize, it can be said that an advantage of
the boot of the invention is to reduce user fatigue or, as a
corollary, to increase user performance, while retaining the
qualities of the boots of the prior art, in particular the
torsional rigidity and flexural flexibility.
[0013] Paradoxically, the boot according to the invention has
successfully reconciled two conflicting characteristics, including
the steering or support accuracy, on the one hand, and comfort, on
the other hand, while reducing the weight of the boot. Indeed, the
shell made of a rigid material, despite its s torsional and
flexural characteristics, also brings a certain comfort. For
example, for a cross-country ski boot, the shell located outside
stiffens the boot, but this shell is sufficiently thin to adapt to
the foot and to wrap the latter with precision. This paradoxically
contributes to making the boot comfortable, despite the use of
rigid materials.
[0014] According to one or more other characteristics of the boot,
taken individually or in combination, [0015] the thickness of the
peripheral wall of the rear cradle is less than 1.5 millimeters,
[0016] the thickness of the peripheral wall of the front cradle is
less than 1.5 millimeters, [0017] the shell includes a front cradle
the blade-shaped portion connecting the rear cradle to the front
cradle, the blade-shaped portion extending in the area of the
metatarsus of the user, a recess being located between the rear
cradle and the front cradle in the area of the blade-shaped
portion, [0018] the rear cradle and the blade-shaped portion are
unitary elements, [0019] the rear cradle and the blade-shaped
portion are separate elements, [0020] the thickness of the
blade-shaped portion in the bending zone is less than 4.0
millimeters, [0021] the thickness of the peripheral wall tapers off
between the bottom and the upper opening, [0022] the minimum width
of a recess of the bending zone is at least greater than 5.0
millimeters, [0023] the minimum width of a recess of the bending
zone is between 20 and 30 millimeters, and is preferably on the
order of 25 millimeters, [0024] the shell is entirely made of
composite materials, and the thickness of the peripheral wall is
between 0.5 and 1.2 millimeters, [0025] the shell is entirely made
of carbon fibers, and the thickness of the peripheral wall is
between 0.5 and 0.8 millimeters, [0026] the peripheral wall at
least is made of glass fibers, and the thickness of said peripheral
wall is between 0.8 and 1.2 millimeters, [0027] the blade-shaped
portion is made of composite materials and includes unidirectional
fibers of the composite material in the bending zone, [0028] the
bending zone defines a front cradle and a rear cradle, the
materials of the front and rear cradles being different from one
another, the blade-shaped portion being made of carbon fibers,
[0029] lightening holes are provided in the rear cradle, [0030] at
least one cradle is made of a plastic material, and the thickness
of the cradle is less than or equal to 1.5 millimeters, [0031] the
bending zone of the blade-shaped portion is thicker than the
remainder of the blade-shaped portion, [0032] the bending zone
comprises fibers which form an angle with the longitudinal axis of
the boot, [0033] the bending zone defines a front cradle and a rear
cradle, the shell comprising the front cradle and the rear cradle,
the shell comprising a means for fixing the front and rear cradles
in the area of an overlapping of the front and rear bottoms of the
cradles, [0034] the bottom of the rear cradle extends beneath the
bottom of the front cradle, the fixing means being arranged beneath
the front cradle, [0035] the front bottom extends beneath the rear
bottom, the fixing means being arranged beneath the rear cradle,
[0036] the fixing means is removable, [0037] the shell is a unitary
element, [0038] the shell comprises a stiffening blade extending at
least beneath the bending zone, said stiffening blade being capable
of assuming an active position in which said stiffening blade
thickens the sole assembly in the bending zone, and an inactive
position in which the end of the stiffening blade is free, [0039]
the free end of the stiffening blade extends rearward of the
bending zone, [0040] the free end of the stiffening blade is
adapted to be retained in the active position by a removable
retaining means, [0041] the shell comprises lateral protective
upright panels in the area of the malleoli, [0042] the bending zone
defines a front cradle and a rear cradle, and the front cradle has
a central upper recess, [0043] the shell comprises through holes
adapted to receive fixing screws, and it comprises inner shoulders
arranged around the through holes, adapted to house the heads of
said fixing screws.
[0044] With respect to the stiffening blade, it should be noted
that the boot according to the invention overcomes the disadvantage
related to the lack of adjustment of the flexural rigidity, by
providing rigidity that is adjustable depending upon the type of
practice. Thus, the same boot can be flexurally flexible in one
case and flexurally rigid in another case, simply by activating a
linkage between the shell and an auxiliary blade.
[0045] Therefore, the shell comprises a blade overlying the sole
assembly and affixed thereto forward of the bending zone, but
independent thereof beneath and rearward of the bending zone. The
primary function of this blade is to stiffen the shell in reverse
bending, that is to say, when the foot moves backward and the front
of the boot is retained on the ski, for example. This is especially
useful for a mountain ski boot, which tends to bend inversely
during support on the upper portion of the boot. The boot devoid of
this blade might then simply break during rear support.
[0046] The second function of this blade is to stiffen the shell
flexurally when the blade is coupled to the shell. The same shell
thus allows obtaining a boot that is flexible in one case and rigid
in another case.
[0047] The invention also relates to a shell provided to be
integral with a boot as mentioned above.
[0048] According to a first embodiment, the bending zone defines a
front cradle and a rear cradle in the shell, and the boot comprises
two straight stays connecting the walls of the rear cradle to the
walls of the front cradle, respectively.
[0049] According to another example of embodiment, the bending zone
defines a front cradle and rear cradle in the shell, and the boot
comprises a Y-shaped stay connecting the walls of the rear cradle
to the front cradle.
[0050] The bending zone enables the ski boot to be flexurally
flexible in the area of the metatarsal joint to allow for foot
rolling movement during skiing. The thickness of the peripheral
wall of the cradle, with a maximum less than 1.5 millimeters, makes
it possible to obtain a ski boot having both required qualities of
rigidity and low weight.
[0051] The cradles are very thin on the lateral and medial
portions, which provide a certain flexibility useful for comfort
and necessary to tighten the foot without weighing down the shell.
In addition, the cradle shapes of the shell enable it to have great
rigidity at the front and rear.
[0052] Due to the composite materials, excellent rigidity and low
weight can be obtained with a very small thickness in the lateral
and medial portions, ranging between 0.5 and 1.2 millimeters. It is
thus possible to obtain ski boots weighing about 300 g per foot,
instead of 600 g to 700 g for a boot of the prior art.
[0053] Furthermore, with the blade-shaped portion having a
thickness with a maximum of less than 4.0 millimeters in the
bending zone being, bending is comfortable in the area of the
metatarsal joint.
[0054] Thus, with a thickness of the peripheral wall of the cradle
being less than 1.5 millimeters and a bending zone formed by
recesses between the cradles, the shell has good torsional rigidity
while having good flexural flexibility and reduced weight.
[0055] The geometry and selection of materials for the shell make
it possible to obtain a boot having good torsional rigidity and
good flexural flexibility, in addition to being comfortable.
[0056] Furthermore, the use of a stiffening blade enables the
latter, in reverse bending, to stiffen the sole assembly in the
active position, and to prevent this reverse bending of the shell.
This is particularly useful for a mountain ski boot, which tends to
bend inversely during support on the collar of the boot. A shell
devoid of the blade might simply break during rear support.
[0057] Thus, the same boot can be used for various practices of
Nordic skiing. The stiffening blade is deactivated to obtain a
flexurally flexible boot more adapted to the so-called classic
practice, and the stiffening blade is activated to obtain a more
flexurally rigid boot that is better suited to practice of the
skating step.
[0058] Depending on the position of the end of the stiffening
blade, the same boot can thus have a different flexural rigidity.
This adjustability is particularly advantageous in competition for
example combining two events, such as a classic event immediately
followed by a skating step event without interrupting the timer.
This avoids the use of hybrid boots in which rigidity is
intermediate between a flexible boot and a rigid boot, and which
would be a rather unsatisfactory compromise in both practices.
[0059] Other advantages and characteristics will become apparent
from reading the description of the invention, and from the annexed
drawing figures, in which:
[0060] FIG. 1 is a perspective view of the lateral side profile of
a Nordic ski boot according to a first embodiment, in a case in
which the inner liner is not arranged in the shell,
[0061] FIG. 2 is a view of the medial side profile of the boot of
FIG. 1,
[0062] FIG. 3 is a bottom view of the boot of FIG. 1,
[0063] FIG. 4 is a perspective view of the lateral side profile of
the shell of the ski boot, according to one of FIGS. 1-3,
[0064] FIG. 5 shows the shell of FIG. 4, in which an inner liner is
inserted,
[0065] FIG. 6 is a perspective view of the right medial profile of
the inner liner of FIG. 5,
[0066] FIG. 7 is a perspective bottom view of a shell on which
zones provided with protections are shown schematically,
[0067] FIG. 8 is a schematic side view of an alternative embodiment
of the shell,
[0068] FIG. 8 bis is a top view of the shell of FIG. 8,
[0069] FIG. 9 is a top view of the shell of FIG. 8,
[0070] FIG. 10 is a cross-sectional view along the line AA of the
blade-shaped portion in the bending zone of the shell of FIG.
8,
[0071] FIG. 11 is a perspective view of the medial profile of a
Nordic ski boot shell according to a second embodiment in the
assembled state,
[0072] FIG. 12 is a perspective top view of the shell of FIG. 11,
in the disassembled state,
[0073] FIG. 13 is a bottom view of the shell of FIG. 11, in the
disassembled state,
[0074] FIG. 14a is a schematic, longitudinal cross-sectional view
of a shell for a Nordic ski boot according to a third
embodiment,
[0075] FIG. 14b is a cross-sectional view of a shell for a Nordic
ski boot according to a fourth embodiment, which is a variation of
the third embodiment,
[0076] FIG. 15a is a schematic cross-sectional view along a
longitudinal median plane of the shell according to a fifth
embodiment,
[0077] FIG. 15b is a bottom view of the shell of FIG. 15a, with the
stiffening blade in the active position,
[0078] FIG. 15c is a cross-sectional view along a longitudinal
median plane of a boot provided with the shell of FIG. 15a fixed to
a ski, with the foot in reverse bending and the stiffening blade in
the active position, the liner not being shown,
[0079] FIG. 15d shows the boot of FIG. 15c fixed to the ski, with
the foot bent and the stiffening blade in the inactive
position,
[0080] FIG. 15e shows the boot of FIG. 15c fixed to the ski, with
the foot bent and the stiffening blade in the active position,
[0081] FIG. 16a is a perspective view of a shell according to a
sixth embodiment,
[0082] FIG. 16b shows a variation of a shell according to a seventh
embodiment, and
[0083] FIG. 17 is similar to FIG. 8, for an eighth embodiment.
[0084] In these drawing figures, identical elements are designated
by the same reference numerals.
[0085] The upper, lower, front and rear, lateral and medial
positions are used with reference to the foot of a user.
[0086] FIGS. 1 to 3 show a ski boot 1 intended for the practice of
Nordic skiing, during which the skier alternatively lifts the heel,
such as when practicing telemark, ski touring, or cross-country
skiing. The inner liner is not shown. In the description, the
various types of skiing enabling the practice of the Nordic skiing
disciplines are generically designated by cross-country skiing, or
even just skiing.
[0087] The boot 1 comprises a shell 2 (FIG. 4), a sealing outer
layer 3 partially enveloping the shell 2, and a collar 4
articulated to the shell 2 (FIGS. 1 and 2).
[0088] More clearly visible in FIG. 4, the shell 2 comprises a
peripheral wall 5 above a sole assembly portion 6 and an upper
opening 7 arranged in the upper portion of the peripheral wall 5
for insertion of the skier's foot.
[0089] The shell 2 is an envelope having a shape adapted to
surround a foot. The shell 2 is relatively rigid but has a bending
zone Z located in the area of the metatarsal joint. The bending
zone Z is formed by recesses in the peripheral wall 5 of the shell
2. The recesses are two lateral and medial zones extending on both
sides of the upper opening 7, from the upper opening 7 to the sole
portion 6. The bending zone Z enables the ski boot 1 to be
flexurally flexible in the area of the metatarsal joint, in order
to enable the rolling movement of the foot during skiing.
[0090] The bending zone Z thus demarcates a front cradle or end
piece toward the tip of the shell 2, and a rear cradle toward the
heel of the shell 2.
[0091] The upper opening 7 of the shell 2 extends at least from the
zone of the ankle to the bending zone Z, which gives a certain
flexibility to the peripheral wall 5 in the area of the rear
cradle, and thereby enables the foot to be tightened and
supported.
[0092] The front cradle makes it possible to protect the toes of
the skier and participate in supporting the foot. The front cradle
can have a central upper recess 8, in the extension of the upper
opening 7, as shown in FIG. 4. It can be seen below that the front
cradle can also be removed and replaced by a simple protective toe
cap without special stiffening function.
[0093] The lateral and medial recesses of the bending zones Z can
have opposite parallel edges, the recesses being for example
slightly angled towards the tip of the shell 2, as shown in FIGS. 4
and 5. In another example shown in FIG. 8, the recesses of the
bending zone Z are flared upward. It is preferred to have recesses
with opposite parallel or upwardly flared edges so that in bending,
the front cradle does not contact the rear cradle.
[0094] The width If of the recesses of the bending zone Z at the
narrowest point (FIGS. 4 and 8) is at least greater than 5.0
millimeters to allow for the bending. The width lf ranges for
example between 20 and 30 millimeters, and is preferably on the
order of 25 millimeters.
[0095] It is further provided that the thickness ep of the lateral
and medial portions of the peripheral wall 5 has a maximum of less
than 1.5 millimeters, which makes it possible to obtain a ski boot
1 having both required qualities of rigidity and low weight.
[0096] The cradles are very thin on the lateral and medial
portions, which provide a certain flexibility useful for comfort
and necessary to tighten the foot without weighing down the shell.
In addition, the cradle-shapes of the shell provide the latter with
great rigidity at the front and rear.
[0097] The shell 2 is for example made entirely of composite
materials, such as carbon fibers, glass or aramid fibers. The
composite materials make it possible to obtain excellent rigidity
and low weight, with a very small thickness in the medial and
lateral portions between 0.5 and 1.2 millimeters. It is thus
possible to obtain ski boots weighing about 300 g per foot, instead
of 600 g to 700 g for a boot of the prior art.
[0098] With a shell made of composite material, the fibers of the
blade-shaped portion 6 can also be provided to be unidirectional in
the bending zone Z.
[0099] As shown in FIG. 8 bis, at least a percentage of the
constituent fibers of the blade-shaped portion are oriented along
the longitudinal direction L of the boot. These fibers are for
example located in the thickness of the blade-shaped portion, that
is to say, apart from the surfaces which demarcate it. It can also
be said that the unidirectional fibers are located in a central
region of the blade-shaped portion, thickness-wise.
[0100] Alternatively, and as shown in FIG. 9, the blade-shaped
portion 6 is made of composite materials, and the fibers of
composite materials are crisscrossed in the bending zone. First
fibers form an angle ranging for example between +40.degree. and
+70.degree. with the longitudinal axis L of the blade-shaped
portion 6; and second fibers form an angle ranging for example
between -40.degree. and -70.degree. with the longitudinal axis L of
the blade-shaped portion 6. For example, the first fibers form an
angle of about 60.degree. with the longitudinal axis L, and the
second fibers form an angle of about -60.degree.. The crisscrossed
fibers make it possible to provide continuity of the torsional
rigidity of the shell 2' in the bending zone Z substantially less
rigid in torsion of the recesses.
[0101] The shell 2, 2' is for example entirely made of carbon
fibers. In this case, good rigidity and low weight can be obtained
with a thickness of the lateral and medial portions ranging between
0.5 and 0.8 millimeters.
[0102] According to another example, at least the peripheral wall 5
is made of glass fibers. In this case, good rigidity and low weight
can be obtained with a thickness of the lateral and medial portions
of the upper portion 5 ranging between 0.8 and 1.2 millimeters.
[0103] To further reduce the weight without sacrificing the
qualities of rigidity, one can provide to arrange lightening holes
in the peripheral wall 5 of the shell 2, forming a grid-like shell
(not shown), for example.
[0104] According to another example, at least the peripheral wall 5
is made of an injected plastic material. In this case, good
rigidity and low weight can be obtained with a thickness of the
lateral and medial portions of the lower peripheral wall being less
than or equal to 1.5 millimeters. The shell 2, 2' is then provided
to comprise lightening holes to ensure low weight while having good
rigidity.
[0105] The materials of the front and rear cradles can also be
envisioned to be different from one another, selected for example
from various composite materials (carbon fiber, glass or aramid
fiber) and/or by associating a composite material with a plastic
material. However, it is preferred that the blade-shaped portion 6
be made of carbon fibers.
[0106] Furthermore, the thickness d of the blade-shaped portion 6
in the bending zone Z is provided to have a maximum of less than
4.0 millimeters, in order to allow for comfortable bending in the
area of the metatarsal joint. FIG. 10 shows a cross-section of the
blade-shaped portion 6 in the bending zone Z. The four millimeters
thickness d represents the maximum thickness between the highest
point and lowest point of the thickness of the blade-shaped portion
6 in the bending zone Z.
[0107] In particular, the thickness ep of the lateral and medial
portions of the wall 5 can also be provided to taper off between
the blade-shaped portion 6 and the upper opening 7. For example,
for a shell 2 made entirely of carbon fibers, the thickness in the
area of the blade-shaped portion 6 can vary and can range between
1.2 millimeters in the vicinity of the blade-shaped portion 6 and
change to about 0.5 millimeters in the area of the upper opening 7.
The thinning of the thickness ep of the peripheral wall 5 locally
increases its flexibility, particularly in the area of the lateral
and medial portions, thereby enabling a progressive and enveloping
tightening of the rear cradle around the foot.
[0108] In this first embodiment, whether it is made of one or more
different materials, the shell 2, 2' is a unitary element, that is
to say, it comprises a single piece. The shell 2, 2' has a uniform
and smooth surface, and the blade-shaped portion 6 and the
peripheral wall 5 are connected continuously. Thus, the shell 2, 2'
is comfortable for the user's foot.
[0109] Thus, with a thickness of the lateral and medial portions of
the peripheral wall 5 being less than 1.5 millimeters and a bending
zone Z formed by recesses in the wall 5 of the shell 2, 2'
extending from the upper opening 7 of the wall 5 to the
blade-shaped portion 6, the shell 2, 2' has good torsional rigidity
while having good flexural flexibility and reduced weight.
[0110] The boot 1 further comprises a front fixing element 9
associated with the blade-shaped portion 6 of the shell 2, upstream
of the bending zone Z (FIG. 3). The front fixing element 9 is
provided with a transverse pivot 10 rotatably assembled to the
front binding to the ski. The front fixing element 9 is for example
screwed into the front cradle of the shell 2. For this, the shell 2
can be provided to have through holes and inner shoulders arranged
around the through holes. The inner shoulders are provided within
the shell 2. The through holes are adapted to receive fixing screws
11. The shoulders are adapted to receive and completely house the
heads of the fixing screw heads (or the nuts). This ensures that
the fixing screws 11 are fully integrated within the shell 2 and
cannot injure the foot of the user.
[0111] To improve user comfort and to ensure good transverse
support of the ankle, the shell 2, 2' can also comprise lateral and
medial protective upright panels 12 on both sides of the malleoli,
to better protect the malleoli of the user. One can further provide
to articulate the collar 4 of the boot 1 on these upright panels
12.
[0112] Furthermore, the rear bottom portion of the blade-shaped
portion 6 (or heel) can define two guiding grooves 48 for the
transverse retention of the boot 1 affixed to the ski binding when
the heel of the boot is supported on the ski.
[0113] The sealing outer layer 3 is made of an impervious,
hydrophobic material to withstand snow, rain and ice, and of an
elastic material to facilitate the insertion of the foot into the
upper opening. It is for example made of a neoprene-based stretch
fabric, a polyurethane layer, or any equivalent material. The
sealing outer layer 3 is for example fixed to the edges of the
blade-shaped portion 6, on the one hand, and to the rear cradle, on
the other hand. The sealing outer layer 3 covers the lateral and
medial recesses of the bending zone Z and a portion of the upper
opening 7. It thus makes it possible to protect the user's
foot.
[0114] The boot 1 also comprises an inner liner 20, for example
made of a polar fabric, received in the shell 2, 2'. The inner
liner 20 is used to provide softness and warmth to the user, and
prevents the foot from rubbing the edges of the shell 2. It also
makes it possible to cover the foot of the user in the bending zone
Z. An example of inner liner 20 is shown in FIGS. 5 and 6.
[0115] In the illustrative example of FIGS. 1 and 2, the boot 1
also comprises two tightening straps 13a, 13b and a band 14. The
band 14 tightens the boot on the foot of the user, obliquely
between the bending zone Z and the rear cradle. The first
tightening strap 13a is adapted to connect the lateral and medial
portions of the rear cradle in the area of the instep. It makes it
possible to adjust the tightening of the rear cradle. The first
tightening strap 13a and the band 14 also make it possible to keep
the sealing outer layer 3 and the shell 2 together on the user's
foot. The second tightening strap 13b is adapted to adjust the
tightening of the collar 4 around the ankle of the user. Of course,
alternatively or complementarily, the boot can include other
tightening means, such as a lace device or any equivalent.
[0116] In order not to unnecessarily weigh down the shell 2, only
certain preferred contact zones are provided with protective
elements to protect the shell 2 and to make it possible to walk
safely. The zones provided with these elements include, for
example, the heel zone 15 defining the guiding grooves 48 and the
front zone 19 of the shell 2, which are the contact zones at the
beginning and at the end of the step, the medial 16 and lateral 17
zones of the bending zone Z, as well as the lower central portion
18 of the bending zone Z, which are preferred support zones of
contact with the ski for the standing position or during foot
rolling movement (FIG. 7). The protective elements 16 and 17 are
provided to protect the bending zone Z, particularly in the area of
the recesses, against impacts or friction in a track in the
snow.
[0117] Thus, the geometry and selection of materials for the shell
2, 2' make it possible to obtain a boot 1 having good torsional
rigidity and good flexural flexibility, in addition to being
comfortable.
[0118] According to a second embodiment shown in FIGS. 11, 12, 13,
14a and 14b, the shell is made of a plurality of distinct elements
assembled together.
[0119] In the first example shown in FIGS. 11, 12 and 13, the shell
20 is made of three elements: the front cradle 21, the rear cradle
22, and the blade-shaped portion 23. The front cradle 21 and rear
cradle 22 are made of glass fibers, for example, and the
blade-shaped portion 23 is made of carbon fibers. The front and
rear cradles 21, 22 have rounded shapes, especially in the bending
zone Z. These three elements 21, 22, 23 are affixed to one another,
for example by gluing, welding, or mechanical assembly between the
lower edges of the cradles and the edge of the blade-shaped portion
23.
[0120] The front fixing element 24 of the boot is visible in FIG.
13. One can also see in FIG. 12 that the heads of the fixing screws
11 are received in the inner shoulders provided inside the shell 20
and do not project therefrom.
[0121] Moreover, in this example, the front fixing element 24
comprises an additional transverse bar 25 set back relative to the
transverse pivot 10. The additional transverse bar can be used as
an option, by being connected to an elastic return means connected
to the ski. This option is more particularly suitable to practice
the alternate step or classic technique, which involves moving in
two parallel tracks.
[0122] According to one example shown in FIGS. 14a and 14b, the
shell 26, 26' is made of two distinct elements assembled together,
i.e., the front cradle 27, 27' and the rear cradle 28, 28'.
[0123] Referring to FIG. 14a, the front cradle 27 comprises a
peripheral wall 29 and a blade-shaped portion 30, and the rear
cradle 28 includes a peripheral wall 31 and a blade-shaped portion
32. The shell 26 further comprises a means 33 for fixing the front
27 and rear 28 cradles in the area of overlap of the front and rear
blade-shaped portions 30, 32.
[0124] The fixing means is removable, for example. For example, the
fixing means 33 is provided to comprise at least one fixing screw.
Thus, it is possible to adjust the ski boot to the skier foot size
and the width of the recesses of the bending zone Z by more or less
advancing the front cradle 27 relative to the rear cradle 28.
[0125] In the example of FIG. 14a, the front blade-shaped portion
30 extends beneath the rear blade-shaped portion 32. The fixing
means 33 comprises two fixing screws which are inserted beneath the
rear peripheral wall 31, into the front blade-shaped portion 30 and
extend into the rear blade-shaped portion 32, thus connecting the
two cradles 27, 28 to one another.
[0126] In the example of FIG. 14b, the rear blade-shaped portion
32' extends beneath the front blade-shaped portion 30'. The fixing
means 33' comprises a single fixing screw which is inserted beneath
the front peripheral wall 29', into the rear blade-shaped portion
32' and extends into the front blade-shaped portion 30', thus
connecting the two cradles 27', 28' to one another.
[0127] Alternatively, the front and rear cradles 27, 28, 27', 28'
are permanently affixed to one another, for example by gluing,
welding, or mechanical assembly.
[0128] It is further possible to insert a flexible layer between
the front and rear blade-shaped portions or bottoms 30, 32, 30',
32'.
[0129] Thus, in either one of these two embodiments, the
blade-shaped portion 30, 32, 30', 32' is not doubled in the bending
zone Z and remains less than 4.0 millimeters to enable bending of
the boot.
[0130] FIGS. 15a, 15b, 15c, 15d and 15e show a fifth embodiment, in
which the shell 34 comprises a stiffening blade 35.
[0131] As can be seen in FIGS. 15a and 15b, the stiffening blade 35
extends at least beneath the bending zone Z. It is adapted to
assume an active position in which it thickens the blade-shaped
portion 36 in the bending zone Z by being superimposed on the
blade-shaped portion 36 (FIG. 15e), and an inactive position in
which the end 37 of the stiffening blade 35 is free (FIG. 15d).
[0132] The free end 36 of the stiffening blade 35 extends for
example toward the rear of the bending zone Z, the front end being
affixed to the blade-shaped portion 36 of the front cradle 38. The
stiffening blade 35 for example is broader in shape toward the
front than toward the rear. The rear side tapers off towards the
free end 37.
[0133] Thus, the stiffening blade 35 is active in reverse bending,
that is to say that when the user leans backwards (arrow F1), and
the front of the boot is maintained on the ski 50, for example
(FIG. 15c). The Stiffening blade 35 stiffens the blade-shaped
portion 36 in the active position and prevents this reverse bending
of the shell 34. This is particularly useful for a mountain ski
boot, which tends to fold backwards (along the direction F1) during
support on the collar 4 of the boot. A shell devoid of the blade
might simply break during rear support.
[0134] The free end 37 can further be retained in the active
position, that is to say, affixed to the blade-shaped portion 36 of
the rear cradle 39 by a removable retaining means.
[0135] The removable retaining means comprises for example a pivot
40 that is manually actuatable by a locking lever 41 affixed to the
pivot 40 (FIG. 15b). The pivot 40 can thus pivot (arrow F2 in FIG.
15b) between the active position, in which it retains the end 37 of
the stiffening blade 35 to the blade-shaped portion 36 (FIG. 15b),
and an inactive position in which the pivot 40 is pivoted apart
from said end 37 (FIG. 15a).
[0136] Because the front end of the stiffening blade 35 is affixed
to the blade-shaped portion 36 of the front cradle 38, the free end
37 of the stiffening blade 35 is biased in the inactive position
during foot rolling movement. Thus, when the shell 34 is bent and
the stiffening blade 35 is in the inactive position, the stiffening
blade 35 is inoperative; it does not contribute to stiffening the
shell 34 which remains flexible in the bending zone due to the
recesses in the bending zone Z and the thin blade-shaped portion 36
(FIG. 15d).
[0137] In the active position, when the shell 34 is bent, the
stiffening blade 35 is kept affixed to the blade-shaped portion 36
at the rear of the bending zone Z by the pivot 40. The thickness of
the blade-shaped portion 36 doubled by the stiffening blade 35
makes the shell 34 more rigid, making it more difficult to bend the
foot (FIG. 15e).
[0138] Thus, the same boot can be used for various practices of
Nordic skiing. The stiffening blade 35 is deactivated to obtain a
flexurally flexible boot more adapted for the so-called classic
practice, and the stiffening blade 35 is activated to obtain a
flexurally rigid boot more suited to practice the skating step.
[0139] Thus, depending on the position of the end of the stiffening
blade 35, the same boot can have a different flexural rigidity.
This adjustability is particularly advantageous for example in a
competition combining two events, such as a classic event
immediately followed by a skating step event without interrupting
the timer. This avoids the use of hybrid boots in which rigidity is
intermediate between a flexible boot and a rigid boot, and which
would be a rather unsatisfactory compromise in both practices. This
principle can also be used in mountain boots to make them rigid and
to enable crampons to be mounted.
[0140] According to a sixth embodiment shown in FIG. 16a, the ski
boot comprises two straight stays 43 connecting the lateral and
medial portions of the rear cradle 44 to the lateral and medial
portions of the front cradle 45. The portions of the front cradle
45 are defined by the ends of the shell 42 between the upper
central recess 8 of the front cradle and the recesses of the
bending zone Z. The portions of the rear cradle 44 are defined by
the ends of the shell 42 between the upper opening 7 of the
recesses of the bending zone Z.
[0141] The stays 43 are formed of a strip of fabric made of
Kevlar.RTM. fibers. The stays 43 are used to prevent the backward
bending of the shell 42 and also contribute to the tightening of
the shell 42.
[0142] According to an alternative embodiment shown in FIG. 16b,
the ski boot comprises a single, generally Y-shaped stay 46. The
stay 46 connects the lateral and medial portions of the rear cradle
44 with the front cradle 47. Unlike the previous variation, the
front cradle 47 is "solid", that is to say, it has no upper central
recess.
[0143] The embodiment proposed in FIG. 17 corresponds to a case in
which the boot 1 is devoid of the front cradle. This means that the
shell includes only the rear cradle and the blade-shaped portion.
Accordingly, the bending zone Z extends from the metatarsus to the
front end.
[0144] In any case, the invention is made from materials and
according to techniques of implementation known to one of ordinary
skill in the art.
[0145] Naturally, the invention is not limited to the embodiments
described above, and includes all technical equivalents that fall
within the scope of the claims that follow.
* * * * *