Note: Descriptions are shown in the official language in which they were submitted.
CA 02497037 2005-02-15
GOALIE SKATE
FIELD OF THE INVENTION
The present invention relates to a goalie skate having a boot made of a
thermoformable
material.
BACKGROUND OF THE INVENTION
1o In hockey, the role of the goalie differs significantly from the role of
the other hockey
players. For example, the goalie spends far more time standing in front of the
net than
skating around the ice rink. In addition, the way in which the goalie stands
and moves is
quite different from the way the other players stand and move.
It is common that during a game of hockey, a goalie might assume an angled
position
wherein the goalie's skates are positioned at oblique angles in relation to
the ice surface.
In other words, the goalie stands such that the blades of the skates are not
vertically
parallel as they would normally be for a defenceman or a forward standing at
rest.
Instead, the goalie's skates are angled away from the goalie's body thereby
widening the
points of contact between the goalie and the ice and bringing the goalie's
knees together.
Furthermore, goalies are often known to adopt a "butterfly position" whereby
their knees
flex and their feet are spread apart in order to cover as much of the lower
portion of the
net as possible.
A deficiency with existing goalie skates is that they may cause discomfort to
goalies
during the course of a game of hockey. For example, a deficiency with existing
goalie
skates is that when the goalie assumes an angled position, the upper edge of
the lateral
side of the skate boot may dig into the lateral side of the goalie's leg.
Obviously, this can
cause the goalie discomfort, and can limit the range of movement available to
the goalie.
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CA 02497037 2011-08-29
Accordingly, there is a need in the industry for a goalie skate that takes
into consideration the
types of movements performed by goalies, in order to provide a more
comfortable and better
designed goalie skate that alleviates at least in part the deficiencies
described above. Moreover,
there is need for a goalie skate that provides the goalie with an improved
range of motion such
that the goalie can more easily assume a "butterfly" position. There is also a
need for a goalie
skate boot in which the toe portion is integrally formed with the medial and
lateral sides of the
boot in order to eliminate the traditional toe cap.
SUMMARY OF THE INVENTION
In accordance with a first aspect, the invention provides a goalie ice skate
comprising: (a) a
boot having an outer shell for receiving a human foot, the foot having a heel,
an ankle with a
medial malleolus and a lateral malleolus, medial and lateral sides, a plantar
surface and toes,
the outer shell being made of a composite sheet comprising a layer of a
thermoformable
material, wherein the composite sheet is thermoformed such that the outer
shell forms: i) a
sole for facing the plantar surface of the foot; ii) a heel portion for
receiving the heel of the
foot; iii) medial and lateral side portions for receiving the medial and
lateral sides of the foot
respectively; and iv) an ankle portion for receiving the ankle of the foot,
the ankle portion
comprising a medial side having a medial upper edge that is a first distance
away from the
sole and a lateral side having a lateral upper edge that is a second distance
away from the sole,
the first distance being greater than the second distance; and (b) a cowling
comprising a toe
portion for protecting the toes, a base, medial and lateral walls and a heel
portion extending
upwardly from the base, and a bottom portion for receiving an ice skate blade,
wherein the
medial and lateral walls, heel portion, toe portion and base define a cavity
for receiving at
least partially the boot.
In accordance with another aspect, the invention provides a goalie ice skate
comprising: (a) a
boot having an outer shell for receiving a human foot, the foot having a heel,
an ankle with a
medial malleolus and a lateral malleolus, medial and lateral sides, a plantar
surface and toes,
the outer shell being made of a composite sheet comprising a layer of a
thermoformable
material, wherein the composite sheet is thermoformed such that the outer
shell forms: i) a
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sole for facing the plantar surface of the foot; ii) a heel portion for
receiving the heel of the
foot; iii) medial and lateral side portions for receiving the medial and
lateral sides of the foot
respectively; and iv) an ankle portion for receiving the ankle of the foot,
the ankle portion
comprising a medial side having a medial upper edge and a lateral side having
a lateral upper
edge and wherein the lateral upper edge is located below the medial upper edge
such that
lateral outward flexion of the foot is eased when the goalie skate is in an
angled position
relative to the ground; and (b) a cowling comprising a toe portion for
protecting the toes, a
base, medial and lateral walls and a heel portion extending upwardly from the
base, and a
bottom portion for receiving an ice skate blade, wherein the medial and
lateral walls, heel
portion, toe portion and base define a cavity for receiving at least partially
the boot.
Furthermore, the present invention relates to a goalie ice skate comprising
(a) a skate boot
comprising an outer shell made of a thermoformable material, the outer shell
being
thermoformed such that it comprises: (i) a heel portion for receiving the heel
of the foot; (ii)
medial and lateral side portions for facing the medial and lateral sides of
the foot respectively;
(iii) an ankle portion for receiving the ankle of the foot; and (iv) a toe
portion for facing the
toes of the foot; and (v) a sole for facing the plantar surface of the foot;
and (b) a rigid shell
comprising a base for receiving the sole of the outer shell, a toe portion for
at least partially
covering the toe portion of the outer shell and a bottom portion for receiving
an ice skate
blade.
The present invention also relates to a goalie ice skate comprising a skate
boot comprising an
outer shell made of a thermoformable material, the outer shell being
thermoformed such that it
comprises: (i) a heel portion for receiving the heel of the foot; (ii) medial
and lateral side
portions for facing the medial and lateral sides of the foot respectively; the
medial and lateral
side portions comprising foldable skirt portions projecting therefrom for
forming a sole for
facing the plantar surface of the
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foot; and (iii) an ankle portion for receiving the ankle of the foot, the
ankle portion
comprising a medial side having a medial upper edge and a lateral side having
a
medial upper edge, the lateral upper edge being located below the medial upper
edge
such that lateral outward flexion of the foot is eased when the goalie skate
is in an
angled position relative to the ground; and a rigid shell comprising a toe
portion for
protecting the toes, a base for facing the sole of the outer shell, medial and
lateral
walls and a heel portion extending upwardly from the base, the medial and
lateral
walls, heel portion, toe portion and base defining a cavity for receiving at
least
partially the skate boot.
to
These and other aspects and features of the present invention will now become
apparent to those of ordinary skill in the art upon review of the following
description
of specific embodiments of the invention in conjunction with the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
A detailed description of examples of implementation of the present invention
is
provided hereinbelow with reference to the following drawings, in which:
Figure 1 is a side view of a right human foot with the integument of the foot
shown in
stippled lines and the bones shown in solid lines;
Figure 2 is a front view of the human foot of Figure 1;
Figure 3 is a perspective view of a goalie skate in accordance with a first
embodiment of
the present invention;
Figure 4 is. an exploded view of the goalie skate of Figure 3.
Figure 5 is a front plan view of the goalie skate boot of Figure 3;
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Figure 6 is a back view of a pair of goalie skates illustrated an upright
position;
Figure 7 is a back view of the pair of goalie skates illustrated in an angled
position;
Figure 8 is a perspective view of a goalie skate in accordance with a second
embodiment
of the present invention;
Figure 9 an exploded view of the goalie skate of Figure 8;
Figure 10 is a perspective view of a goalie skate in accordance with a third
embodiment
of the present invention;
Figure 11 an exploded view of the goalie skate of Figure 10;
Figure 12 is a top perspective view of an outer shell in accordance with
another
embodiment;
Figure 13 is a bottom perspective view of the outer shell of Figure 12; and
Figure 14 is a perspective view of a thermoforming apparatus.
In the drawings, embodiments of the invention are illustrated by way of
example. It is to
be expressly understood that the description and drawings are only for the
purposes of
illustration and as an aid to understanding, and are not intended to be a
definition of the
limits of the invention.
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DETAILED DESCRIPTION OF THE EMBODIMENTS
To facilitate the description, any reference numerals designating an element
in one
figure will designate the same element if used in any other figures. In
describing the
embodiments, specific terminology is resorted to for the sake of clarity but
the
invention is not intended to be limited to the specific terms so selected, and
it is
understood that each specific term comprises all equivalents.
Shown in Figures 1 and 2 is a typical human foot F that has toes T, a plantar
surface PS,
a medial side MS and a lateral side LS, a heel H, an Achilles tendon AT and an
ankle A
having a lateral malleolus LM and a medial malleolus MM, the lateral malleolus
LM
being at a lower position than the medial malleolus MM.
Referring to Figures 3 to 7, a first embodiment of a goalie skate is
identified by the
reference numeral 1. The goalie skate I has a skate boot 10 and a rigid shell
20. The
rigid shell 20 has a toe portion 21 for covering at least partially the toe
portion of the
boot 10, a base 25 for receiving the bottom surface of the skate boot 10, and
a bottom
portion 23 with an ice skate blade receiving portion 27 for receiving an ice
skate blade
18. The ice skate blade receiving portion 27 may comprise a longitudinal slot
for
receiving the blade 18 (see Figures 6 and 7). The bottom portion 23 may also
comprise
pedestals 29 connecting the base 25 and the ice skate blade receiving portion
27.
Moreover, the rigid shell 20 may comprise a medial wall 31, a lateral wall 33
and a heel
portion 35, the walls 31, 33 and the heel portion 35 extending upwardly from
the base
25.
As seen in Figures 3 and 4, the heel portion 35, the walls 31, 33, the toe
portion 21 and
the base 25 define a cavity for receiving at least partially the skate boot
10. The rigid
shell 20 may be a cowling as illustrated in Figures 3, 4, 6 and 7. It is
however understood
that the rigid shell may be integrally formed with the skate boot in another
embodiment.
As shown in Figure 4, the skate boot 10 comprises an outer shell 16 that is
made of a
thermoformable material. As used herein, the expression "thermoformable
material"
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CA 02497037 2005-02-15
refers to a material that is capable of softening or fusing when heated and of
hardening
again when cooled. Some non-limiting examples of different types of
thermoformable
material comprise ethylene vinyl acetate (EVA) foam, polyethylene foam,
polystyrene
foam, polypropylene foam and thermoformable materials sold under the trade-
marks
MEGABIX , SURLYN , SONTARA , FORMO500 , BYLON , MOSOCA and
NYLON 66.
The outer shell 16 is thermoformed such that it comprises a heel portion 12
substantially
cup shaped for following the contour of the heel H, medial and lateral side
portions 26,
28 for facing the medial and lateral sides MS, LS of the foot F, respectively,
and an
ankle portion 22 for receiving the ankle A. The ankle portion 22 may have
respective
medial and lateral cup-shaped depressions 36, 38 for receiving the respective
medial and
lateral malleoli MM, LM. The lateral cup-shaped depression 38 is located
slightly lower
than the medial cup-shaped depression 36 for conforming to the morphology of
the ankle
A. Naturally, the ankle portion 22 would not have cup-shaped depressions for
receiving
the malleoli should such ankle portion does not cover such malleoli. The ankle
portion
22 may follow the rear profile of the Achilles tendon AT.
The medial and lateral side portions 26, 28 comprise respective skirt portions
60, 62 for
forming a sole 14 for facing the plantar surface PS. The skirt portions 60, 62
are adapted
to be folded inwardly so as to be affixed together to form the sole 14. As
shown in
Figure 4, the skirt portions 60, 62 are affixed together via stitching 65
along a
longitudinal central line. The medial and lateral skirt portions 60, 62 may
have equal
widths, such that when folded inwardly they are affixed together along a
central
longitudinal axis of the outer shell 16. It should be understood, however,
that the medial
and lateral skirt portions can be of different widths, such that when they are
folded
inwardly, they are affixed together along a longitudinal line that is closer
to either the
medial side portion 26 or the lateral side portion 28.
It should be understood that the skirt portions 60, 62 may be affixed together
in a variety
of different manners without departing from the spirit of the invention, such
as via
adhesive, thermal bonding, piping, zipper, staples and a projection/groove
arrangement.
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Alternatively, the medial and lateral skirt portions 60, 62 could be affixed
together via
interlocking components that fit together in order to affix the two skirt
portions together.
For example, one of the skirt portions can include an arrangement of grooves,
and the
other skirt portion can include an arrangement of corresponding projections
that are able
to interlock with the grooves. As such, by interlocking the corresponding
grooves and
projections, the medial and lateral skirt portions can be affixed together.
The skate boot 10 may further comprise an inner lining 54 having a surface
intended for
contact with the heel H, the ankle A and the lateral and medial sides LS, MS
and a
l0 footbed 64 adapted to be inserted within this skate boot. The inner lining
54 may be
glued and/or stitched to the inner surface of the thermoformed shell 16. The
footbed 64
has a sole portion 66 for receiving the plantar surface PS of the foot F, and
a padding
wall 68 that surrounds the heel H and faces the medial side MS and lateral
side LS. The
footbed 64 can be inserted into the thermoformed shell 16 in order to sit upon
the sole 14
formed either by the two foldable skirt portions 60, 62, or against a sole
that is a separate
component.
The skate boot 10 may also comprise a tongue 24, a toe cap 30 and two narrow
bands 58
that are secured to the upper portion of each of side portions 26, 28. The
narrow bands
58 are made of fabric, textile or leather. In an alternative embodiment, a
single
continuous band that covers the upper portion of each of side portions 26, 28
and wraps
around the rear of the ankle portion 22 can be used instead of two distinct
bands 58.
Apertures 59 are punched through the narrow bands 58, the thermoformed shell
16 and
the inner lining 54. Once punched, the apertures 59 are reinforced by metallic
rivets 61
or any suitable means as is well known in the art of footwear construction.
The tongue
24 and toe cap 30 may be affixed to the thermoformed shell 16. In a non-
limiting
embodiment, the toe cap 30 and the tongue 24 are pre-assembled prior to
installation to
thermoformed shell 16. The tongue 24 is affixed to the toe cap 30 and extends
upwardly
and rearwardly from the toe cap 30 for covering the forefoot of the foot F.
The frontal
3o edge of the tongue 24 can be sewn directly to the toe cap 30 or can be
fixed in an
alternative manner known in the art. The toe cap 30 can be secured to the
thermoformed
shell 16 by sewing both sides of toe cap 30 to each of side portions 26, 28.
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In a non-limiting embodiment, the thermoformed shell 16 is made of a single
integral
component. However, it should be understood that the thermoformed shell 16
could also
be made of multiple sections without departing from the spirit of the
invention. For
example, the thermoformed shell 16 could be made from separate medial and
lateral side
portions that are affixed together to form a shell having the three-
dimensional shape
shown in Figure 4. In a non-limiting example of implementation, the
thermoformed shell
16 is made of a composite sheet comprising a layer of thermoformable foam.
In an embodiment not shown in the drawings, the skate boot 10 may have a rigid
ankle
support which is positioned between the thermoformed shell 16 and the inner
lining 54.
The rigid ankle support is adapted for providing more support and rigidity in
the general
ankle area. It should be understood that in the cases where the thermoformed
shell 16 is
rigid enough to support the ankle A, there is no need to include a rigid ankle
support.
Referring to Figures 3 to 7, the ankle portion 22 of the outer shell 16
comprises a medial
side 32 having an upper edge 40 and a lateral side 34 having an upper edge 42.
As best
shown in Figure 5, the upper edge 40 is a first distance D1 away from the sole
14, and
the upper edge 42 is a second distance D2 away from the sole 14, the distance
D 1 being
greater than the distance D2. The medial and lateral sides 32, 34 have
therefore different
heights since the lateral wall 34 does not extend as high up as the medial
wall 32. In
other words, the lateral upper edge 42 is located below the medial upper edge
40, the
difference of height being identified as AD. Note that the skate boot 10 shown
in
Figures 3 to 5 is for a right foot. In a non-limiting embodiment, the
difference of height
AD may be between 5 to 10 mm. In an alternative non-limiting embodiment, the
difference of height OD may be between 10 to 20 mm.
It is understood that the outer shell 16 and the inner lining 54 may have
medial and
lateral sides of corresponding different heights such that the skate boot 10,
once
assembled, has also medial and lateral sides of different heights as
illustrated in Figure 3,
5, 6 and 7. The medial and lateral sides 32, 34 may cover the malleoli as
illustrated
herein; however, it is also understood that the medial and lateral sides may
have
respective medial and lateral upper edges that are located just below the
medial and
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CA 02497037 2005-02-15
lateral malleoli respectively.
Figure 6 is a back view of a pair of goalie skates illustrated in an upright
position. As
shown in that figure, the upper edges 40 of the medial walls 32 are higher in
relation to
the ground 100 than the upper edges 42 of the lateral walls 34. Shown in
Figure 7, is the
same pair of goalie skates positioned in an angled position, wherein the
blades 18 are
positioned at an oblique angle 0 in relation to the ground 100. By having a
goalie skate
boot that has the lateral upper edge 42 located below the medial upper edge
40, the
lateral outward flexion of the foot is then eased when the goalie skate is in
the angled
position shown in Figure 7.
Figures 8 and 9 show a second embodiment of a goalie skate 100 wherein the
skate boot
110 has an outer shell 116 that is made of a thermoformable material and is
thermoformed such that it comprises a heel portion 112 substantially cup
shaped for
following the contour of the heel H, medial and lateral side portions 126, 128
for facing
the medial and lateral sides MS, LS of the foot F, respectively, an ankle
portion 122 for
receiving the ankle A, the ankle portion 122 comprising medial and lateral
upper edges
140, 142, and a toe portion 130 facing the toes T of the foot F. Hence,
because outer
shell 116 comprises an integrated toe portion 130 facing the toes T, there is
no need for a
separate toe cap 30 that is secured to the thermoformed shell 16 as
illustrated in Figure 4.
The ankle portion 122 may have respective medial and lateral cup-shaped
depressions
136, 138 for receiving the respective medial and lateral malleoli MM, LM. The
lateral
cup-shaped depression 138 is located slightly lower than the medial cup-shaped
depression 136 for conforming to the morphology of the ankle A.
Moreover, as for the outer shell 16, the lateral upper edge 142 of the outer
shell 116 is
located below the medial upper edge 140, the difference of height being
identified as
OD. Note that the skate boot 110 is for a right foot. In a non-limiting
embodiment, the
3o difference of height AD may be between 5 to 10 mm. In an alternative non-
limiting
embodiment, the difference of height AD may be between 10 to 20 mm. Again, by
having the lateral upper edge 142 located below the medial upper edge 140, the
lateral
CA 02497037 2005-02-15
outward flexion of the foot is then eased when the goalie skate 100 is in the
angled
position.
Figures 10 and 11 show a third embodiment of a goalie skate 200 wherein the
skate boot
210 is identical to the skate boot 110 and wherein the components are
designated by the
same reference numerals. The only difference resides in the construction of
the outer
shell 216 in which the ankle portion 222 comprises medial and lateral upper
edges 240,
242 that are at the same height. Moreover, the skate boot 210 has an inner
lining 254
having medial and lateral upper edges that are also at the same height.
Figures 12 and 13 show another outer shell 316 that is thermoformed such that
it
comprises a heel portion 312 substantially cup shaped for following the
contour of the
heel H, medial and lateral side portions 326, 328 for facing the medial and
lateral sides
MS, LS of the foot F, respectively, an ankle portion 322 for receiving the
ankle A, and a
toe portion 330 facing the toes T of the foot F. Again, because the outer
shell 316
comprises an integrated toe portion 330 facing the toes T, there is no need
for a separate
toe cap 30 that is secured to the thermoformed shell 16 as illustrated in
Figure 4. A sole
314 is integrally formed with one of the medial side portions (the medial side
portion
326 as shown in Figures 12 and 13) and the medial and lateral side portions
326, 328
may be affixed together at the rear and along the sole 314.
In order to manufacture the outer shell 16, a pre-cut sheet of thermoformable
material
may be inserted in the cavity of one of a male-female mold. The male and
female
portions of the molds define the inner and outer surfaces of outer shell 16
respectively.
The pre-cut sheet is aligned and temporarily secured to one of the mold
portions using
any suitable means to accurately position the pre-cut sheet within the mold
and
maintain same in position when the mold is closed. Once the mold is closed
over the
pre-cut sheet, the mold is heated up to the thermoforming temperature of the
pre-cut
sheet and male and female portions are pressed against the pre-cut sheet.
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The pre-cut sheet of thermoformable material may be a composite sheet
comprising
layers of different thermoformable materials. It is understood that the pre-
cut sheet
can be thermoformed with a pre-cut sheet of the inner lining 54, instead of
securing
the inner lining 54 to outer shell 16 after the thermoforming operation.
Naturally, the
material of the inner lining 54 must be selected from materials that may
sustain the
thermoforming temperature of the outer shell 16.
In a preferred embodiment of the invention, heat and pressure are applied
simultaneously for a period of 15 seconds to 2 minutes after which the mold is
allowed to cool down so that the pre-cut sheet will set to the three-
dimensional shape
defined by the male and female portions of the mold. Preferably, heat and
pressure are
applied simultaneously for a period of 45 seconds to 1 minute. The applied
heat is
generally between 250 F and 350 F, with the preferred temperature being
approximately 325 F. The applied pressure is generally between 75 psi and 150
psi,
with the preferred pressure being approximately 125 psi. It is understood that
the
amount of time, temperature and pressure may be different if a cooled mold is
used.
Instead of using a male-female mold, an apparatus 72 as shown in Figure 14 may
be
used for thermoforming a pre-cut sheet of thermoformable material into the
shape of
the outer shells 16, 116, 226, 326. The pre-cut sheet of thermoformable
material may
be a composite sheet comprising layers of different thermoformable materials.
The
sheet may be made of thermoforming materials such as those sold under the
trade-
mark MEGABIX (a core of extruded SURLYN , a backing of SONTARA and a
hot melt coating; thickness of 0.95 mm), FORMO500 (non woven polyester with a
core of extruded polyolefinic, stiffening layers of synthetic latex on each
side and an
ethylene vinyl acetate hot melt adhesive on one side; thickness of 1.50 mm),
BYLON (a nylon multifilament with a backing of black saturated needle punched
polyester nonwoven and a face coating of non-fray urethane) and MOSOCA
(NYLON 66 with a core of SURLYN and a PU coating). The composite sheet may
3o also be made of a first sheet of polyethylene high density (HDPE) foam; a
second
sheet of thermoplastic; and a third composite sheet made of a first layer of
cotton, a
second layer of surlyn fibers, a third layer of a mesh of nylon fibers and a
coating.
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The apparatus 72 comprises a supporting frame 74 having an outer shell
traverse and two
pillars 76A and 76B. The two pillars 76A and 76B are joined together at mid-
height by a
ledge 78 that contains a control panel (not shown) with control buttons (not
shown) for
enabling an operator to control the apparatus 72. In the specific embodiment
shown, the
ledge 78 surrounds a last 80 that is supported by a movable support 82. The
movable
support 82 is a hydraulic or pneumatic piston cylinder 84 that is movable up
and down in
a vertical direction, as indicated by arrow A. It should be understood that
lasts 80 of
different shapes and sizes can be installed on apparatus 72, in order to
manufacture outer
shells of different shapes and sizes.
The apparatus 72 further comprises a pair of clamps 86A, 86B that are mounted
to the
outer shell traverse and positioned directly above last 80. Clamps 86A, 86B
are adapted
to open and close, as indicated by arrows B in order to clamp around the last
80. The
clamps 86A, 86B comprise pressure pads 88 for receiving the sheet of
thermoformable
material. In addition, each of the clamps 86A, 86B comprises a bladder (not
shown)
having an inflated membrane and a fluid pressure delivery circuit (not shown)
for
causing the membrane to inflate, such that it is able to surround the last 80
during use.
In operation, the sheet of thermoformable material is placed on the last 80
and is
accurately positioned and secured in place via the use of clips (not shown).
Once the
sheet is securely in place, the operator activates the apparatus 72 which
causes the
piston-cylinder 84, and therefore the last 80, to raise up between the two
open clamps
86A, 86B. When the last 80 reaches the pressure pads 88, the piston-cylinder
84 reaches
a set value and stops. It should be understood that in an alternative
embodiment, the last
80 can remain stationary, and the clamps 86A, 86B can be connected to piston-
cylinders
for lowering the clamps 86A, 86B around the last 80.
Once the last 80 is positioned between clamps 86A, 86B, the clamps 86A, 86B
begin to
close thereby causing the pressure pads 88 to apply an initial pressure to the
sheet of
thermoformable material situated on the last 80. When the clamps 86A, 86B are
completely closed, the bladders are then inflated by air or liquid injection,
which forces
the flexible membranes of the bladders to encircle the sheet around the last
80 and apply
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pressure thereto. Once the pressure within the bladders has reached a set
value wherein
the bladder membranes apply an even pressure to the sheet, the pressure is
maintained
for a certain amount of time, and is then released.
In a non-limiting example of implementation, a pressure between 30 psi and 120
psi is
maintained around the last for approximately I to 2 minutes. In addition to
the pressure,
heat is also applied to the sheet of thermoformable material. The applied heat
is
generally between 250 F and 550 F, with the preferred temperature being
approximately
450 F. Once heated, the sheet becomes malleable and, as such, is able to
acquire the
three-dimensional shape applied to it by the last 80. The clamps 86A, 86B are
afterwards
opened up and the last 80 is lowered by the piston cylinder 84 to its original
position.
By utilizing different grades of thermoformable material, different
thermoformable
materials or the same material with different density, the designers are able
to vary the
mechanical properties of the outer shells 16, 116, 216, 316.
A last may be inserted into the inside cavity of the outer shell in order to
complete the
construction of the boot. The last enables the outer shell to maintain its
shape when
skirt portions 60, 62 are folded and affixed together. As shown in Figure 4,
the skirt
portions 60, 62 may be affixed together via stitching 65 along a longitudinal
central
line. As indicated previously, the skirt portions 60, 62 may be affixed
together in a
variety of different manners without departing from the spirit of the
invention, such as
via adhesive, thermal bonding, piping, zipper staples and a projection/groove
arrangement. Once the skirt portions 60, 62 are firmly attached together and
the boot
has acquired its final shape, a light sanding of the folded skirt portions 60,
62 may be
performed to partially even the lower surface of the boot and provide a flat
surface on
which the rigid shell 20 can be glued or nailed.
Alternatively, an insole may be positioned inside the skirt portions 60, 62.
It is
understood that the insole is an optional component and may not be required if
the
rigidity of the skirt portions 60, 62 is sufficient. Once the assembly is
completed, the
boot is placed upside down into a lasting machine. Glue is first applied to
the bottom
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surface of the insole along its periphery. Skirt portions 60, 62 are then
folded over the
last onto the bottom surface of the insole. Once folded, skirt portions 60, 62
are
bonded to the insole by the glue that was previously laid on the bottom
surface of the
insole. The skirt portions 60, 62 are further nailed, stitched, or tacked all
around the
insole to provide the necessary mechanical grip and allow the glue to properly
set
between the skirt portions 60, 62 and the insole. Once the skirt portions 60,
62 are
firmly attached to the insole and the boot has acquired its final shape, a
light sanding
of the folded skirt portions 60, 62 may be performed to partially even the
lower
surface of the boot and provide a flat surface on which the rigid shell 20 can
be glued
or nailed.
The above description of embodiments should not be interpreted in a limiting
manner
i
since other variations, modifications and refinements are possible within the
spirit and
scope of the present invention. The scope of the invention is defined in the
appended
claims and their equivalents.
