Note: Descriptions are shown in the official language in which they were submitted.
21922~2
HOCKEY SKATE BOOT HAVING A CONPOSITE SOLE
Field of the Invention
The present invention relates to a skate, and more
particularly to an ice hockey or roller hockey skate boot having
a sole comprising a composite material.
Background of the Invention
Conventional ice hockey skates comprise a boot and a blade
assembly. The boot itself comprises an upper portion fastened to
a sole. The upper portion encircles the dorsal surface of the
foot, the ankle, and the lower part of the calf of the skater,
while the sole registers with the plantar surface of his foot.
The blade assembly comprises a blade holder secured to the ice-
facing surface of the sole and the blade itself. Thus, the sole
provides an interface between the various other portions of the
skate.
When the skater is skating, the force generated by his
muscles is transmitted from his body through his foot to the sole
of the skate to the blade assembly and finally to the ice.
A sport such as ice hockey requires the skater to be able to
quickly accelerate and decelerate and make rapid and precise turns
and changes in skating direction. The skater accomplishes these
manoeuvres by altering the portion of the blade which is in
contact with the ice, by shifting his weight rapdily from foot to
foot, and by varying the amount of force he generates. In order
to allow for increased control over the execution of such
manoeuvres, conventional ice skates for use in these sports are
constructed of lightweight materials to reduce inertial forces and
to increase responsiveness. Moreover, the skate boot soles and
blade assemblies of such skates have been designed to be both
flexible and resilient thereby allowing the skater to vary the
portion of the blade contacting the ice at a greater speed, and to
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flex the blade precisely to the desired position. The blades
themselves are curved.
At the same time, in order to maintain balance and control,
both while skating straight and while turning or changing
direction, the skater must be able to "feel" the ice beneath him,
i.e. he must be able to accurately judge the reaction force of the
ice below.
For these reasons force should be transmitted from the foot
of the skater to the skate and to the ice, and vice versa~ without
any attenuation in the magnitude thereof, except for that
necessary to flex the boot sole and blade assembly. In this
respect, the components of the skate along the force transmission
path, including the sole, must be as efficient transmitters as
possible.
The material used in the fabrication of conventional ice
hockey skate boot soles is thermoplastic rubber (butadiene-
styrene). This material was selected by skate manufacturers over
the years as it is relatively light in weight and is moderately
flexible and resilient. Conventional teaching was that it was
well suited for its function as the desired goals were met.
There is however, a constant effort on the part of skate
manufacturers to improve ice hockey skate performance. As part of
this effort it was hoped that a substitution of thermoplastic
rubber by a material which was lighter in weight while still being
flexible and resilient might provide some such improvement.
Composite materials have been used by skate manufacturers
over the years to manufacture ice speed skating skates. Composite
materials are materials in which two or more distinct substances
such as metals, glass, ceramics, or polymers are combined, with or
without chemical reaction, to produce a material with structural
or functional characteristics different from the individual
constituents. The constituents retain their individual
characteristics and are distinguishable on a microscopic scale.
Typically one constituent is classified as the reinforcement and
- ~192292
the other as the matrix. The matrix binds the reinforcement
together and contributes to the distribution of the load.
Ice speed skating skates are, however, of a completely
different construction than those used for ice hockey. Such
differences are owing to the differences in the sports themselves.
Ice speed skating is sport wherein the object is to travel a
certain distance (e.g. one kilometre) as quickly as possible, the
skater completing the required distance in the fastest time being
declared the winner. The sport generally takes place on an oval
ice track similar in shape to that used in track-and-field events.
Thus the bulk of the distance that the skater must travel is
comprised of straight lengths, such lengths being separated by
sweeping turns the curvature of which is relatively open and
smooth as compared with the precise, tight turns required of ice
hockey players. The movements of the athletes in each sport are
thus completely different, that of speed skaters involves long
gliding strides on each foot, whereas that of an ice hockey player
involves rapid shifting from foot to foot. For these reasons, ice
speed skating skates are designed to allow the maximum amount of
force generated by the skater to be transmitted to the ice. Thus,
the blade is much longer than that of an ice hockey skate and is
flat so that the entire skatable surface of the blade is
simultaneously in contact with the ice surface to allow for
relatively long gliding periods. The sole and blade assembly are
constructed so as to be as rigid as possible so as to minimize
flexion of the blade and an accompanying loss of force generated,
the weight thereof is relatively unimportant. Flexibility of the
sole of such a skate is completely undesirable.
In order to achieve these desired characteristics soles
specific to this type of skate have been constructed. The result
is a multi-layered shell-shaped sole which is hard, rigid and
thick, and contains many solid materials such as metal. One or
more of the layers may be a composite material which used to
provide additional strength to the sole to aid in the elimination
of the flexing of the final product. Conventional experience has
thus taught that composite materials should be employed in ice
~192~92
skate sole construction to eliminate flexibility where rigidity of
the sole and blade assembly is desired.
Nonetheless, more or less by chance, a prototype ice hockey
skate boot having a sole comprised of a single layer of composite
material was fabricated and tested. While the prototype skate was
indeed lighter in weight, it was soon recognised that this sole
yielded a skate with greatly improved performance over
conventional skates. The prototype allowed the skater to more
precisely control his movement on the ice. It was then realised
that the conventional thermoplastic rubber is compressible when
the skate is in use and absorbs some of the force being
transmitted to the ice by the skater. This sole causes the skater
to feel a heretofore unrecognised slight "spongy" feeling, reducing
both his feel of the ice and his control over the flexion of the
skate blade assembly. To professional and very experienced
amateur ice hockey players this loss of feeling and control is
significant.
Roller hockey is a relatively new sport, having become much
more common with the recent increase in popularity of in-line
roller skating as leisure time activity or as a means of travel.
The movements of roller hockey players resemble to those of ice
hockey, and thus the requirements of roller hockey skates are
similar to those of their ice hockey cousins.
The first generation of roller hockey skates are simply an
ice hockey skate boot with a simple wheel frame from a general in-
line roller skate attached. While such frames are generally
inflexible, it is foreseen that advancements in roller hockey
skate technology may provide for skates having flexible frames
similar to the blade assemblies of their ice hockey counterparts.
Such frame constructions would give roller hockey players the more
precise control over their manoeuvres that ice hockey players
currently enjoy.
2192292
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Object and Statement of the Invention
It is therefore an object of the present invention to provide
an ice hockey skate boot or a roller hockey skate boot having a
sole which is flexible, resilient, and substantially
incompressible.
It is a further object of the present invention to provide an
ice hockey skate or a roller hockey skate including a boot having
a sole which is flexible, resilient, and substantially
incompressible.
As embodied and broadly described herein the present
invention provides a hockey skate boot comprising:
(a) an upper portion for receiving the foot of a skater; and
(b) a sole, the sole including a fibre-reinforced matrix,
and the sole, when the boot is in use by a skater,
being:
(i) flexible,
(ii) resilient, and
(iii) substantially incompressible.
A hockey skate boot sole of the present invention is
comprised of a relatively thin sheet of a fibre-reinforced matrix;
such fibre-reinforced matrices being conventionally known as
composite materials. Both the fibres and the matrix of which the
composite material is formed may be one of a number of materials.
Classes of materials commonly used for reinforcement are
glasses, metals, polymers, ceramics and graphite. The
reinforcement can be in many forms, such as continuous fibres or
filaments, chopped fibres, woven particles or ribbons. The
criteria for selecting the type and form of reinforcement will
vary in accordance with the design requirement for the composite,
as is within the competence of those skilled in the art. However,
criteria for a generally desirable reinforcement include high
strength, high modulus, low weight, low cost, ease of fabrication
and environmental resistance.
219229~
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In addition to the reinforcement materials, the other major
component of any composite material is the matrix. The matrix
binds the reinforcement together and enhances the distribution of
the applied load within the composite. Polymeric materials are
widely used as matrix materials. The two general types of
polymers which are generally employed in composite materials are
thermosetting and thermoplastic. The principal differences
between them is the degree of cross-linking and response to
elevated temperature. Thermosetting resins or polymers are
extensively cross-linked and undergo irreversible changes heated
or reacted with a selected catalyst or curing agent. In contrast
thermoplastic materials are generally not as cross-linked and
soften as they are heated. After being exposed to heat they
return to their original condition when cooled below their melting
temperature.
The properties of the composite material are derived from
matrix characteristics in combination with the inherent properties
of the reinforcement material along with the form and amount of
reinforcement used.
A skate boot of the present invention is preferably comprised
of a relatively thin sheet (0.04" to 0.10") of composite material
which is both lightweight and strong, as both characteristics are
desirable in a hockey skate boot sole. Reduced weight is desired
so as to minimize inertial forces and to reduce player fatigue.
Strength is desired so as to prevent the sole from being torn
apart or ripped when the skate is in use. In this respect it has
been determined that an average 200 pound professional ice hockey
player may exert a peak force of up to 500 pounds on the skate.
Heavier players may exert even greater peak forces of
approximately 2.5 times their weight. Serving as an interface
between the various other skate components, boot soles must be
able to withstand such stresses without becoming ripped or torn
apart.
Composite materials have the further advantage in that they
may selected so as to form a sole which is both "flexible" and
"resilient", two characteristics which are required of a hockey
2192292
skate boot sole of the present invention. In the present context
a material should be considered to be flexible where it is able to
be bent from its original shape without breaking, and resilient
where it will spring back to its original shape after having been
flexed (as opposed to compressed). It should be appreciated that
a skate boot sole of the present invention need only have these
characteristics when incorporated within a hockey skate, and then
only when that skate is under normal use by a player for whom such
a skate is intended.
Moreover, a boot sole of the present invention need only be
flexible within the range of flexibility required by the blade
assembly which is attached to the boot. In this manner the boot
sole and blade assembly may cooperate to enable the skater to vary
the conformation of the blade and alter the portion of the blade
which is in contact with the ice. It will be appreciated that for
the most part it is torsional flexibility of the sole which is
required, the sole should be longitudinally flexible, however the
extent of which which is required is not as great. It will
further be appreciated that flexibility of the sole to extent
beyond that required by the blade assembly is not required nor is
it relevant in the context of the present invention. It may be
that the boot sole is flexible beyond that point, it is no longer
flexible (becomes stiff) or even breaks, although the latter is
not preferred.
Similarly, a boot sole of the present invention need only be
resilient up to the point to which it must be flexible. It is not
necessary that it be resilient beyond that point, given that under
normal skating conditions it will never be flexed therebeyond.
The composite material must also be selected so as to be
"substantially incompressible". In the context of the present
specification a hockey skate boot sole will be substantially
incompressible where, during the normal use of a hockey skate in
which the boot sole has been incorporated, by a skater for whom
such a skate is intended, the thickness of the composite material
which the sole comprises is not appreciably reduced.
2192292
Advantageously, the matrix is comprised of a thermosetting
resin or of a thermoplastic resin.
Preferably, the matrix is comprised of a resin selected from
the group consisting of an epoxy, a polyamide, an acrylic, ABS
(acrylonitrile-butadiene-styrene copolymer), polypropylene, and
polyethylene, and the fibres are comprised of a material selected
from the group consisting of glass, carbon, and KevlarTM and are
randomly oriented, undirectionally oriented or bidirectionally
oriented.
Preferably, the sole includes a raised portion.
As embodied and broadly described herein the present
invention also provides an ice hockey skate comprising:
(a) a boot for receiving a foot of a skater, the boot
including an upper portion and a sole, the sole
comprising a fibre-reinforced matrix, and the sole, when
the ice-hockey skate is in use by a skater, being:
(i) flexible,
(ii) resilient, and
(iii) substantially incompressible; and
(b) a flexible blade assembly attached to the sole of said
boot, said blade assembly comprising a blade holder and
a blade.
A blade assembly is flexible for present purposes where it is
capable of being bent out of its original shape during normal
course of use of a skate in which it is incorporated by a skater
for whom it is intended.
It should understood that a blade assembly is considered to
be attached to a sole in the context of the present invention if
it is fastened thereto or formed integrally therewith. In this
respect, any portion of a skate which forms an interface between
the blade assembly and the boot upper will be considered to be the
sole.
- 2192292
As embodied and broadly described herein the present
invention further provides a roller hockey skate comprising:
(a) a boot for receiving a foot of a skater, the boot
including an upper portion and a sole, the sole
comprising a fibre-reinforced matrix, and the sole, when
the roller hockey skate is in use by a skater, being:
(i) flexible,
(ii) resilient, and
(iii) substantially incompressible; and
(b) a flexible frame attached to the sole of said boot.
A frame is flexible for present purposes where it is capable
of being bent out of its original shape during normal course of
use of a skate in which it is incorporated by a skater for whom it
is intended.
It should understood that a frame is considered to be
attached to a sole in the context of the present invention if it
is fastened thereto or formed integrally therewith. In this
respect, any portion of a skate which forms an interface between
the frame and the boot upper will be considered to be the sole.
Other objects and features of the invention will become
apparent by reference to the following description and the
drawings.
Brief Description of the Drawings
A detailed description of preferred embodiments of the
present invention is provided hereinbelow with reference to the
following drawings, in which:
Figure 1 is a perspective view of an ice hockey skate
including a skate boot of the present invention;
Figure 2 is a side elevational view of the skate, having a
portion of the heel area of the skate boot removed to show its
construction;
21~2292
Figure 3 is a perspective view of the skate, having a portion
of the toe area of the skate boot removed to show its
construction;
Figure 4 is a front sectional view of the skate, exploded to
show the various components thereof;
Figure 5 is a front sectional view of the skate similar to
Figure 4, except that the components have been illustrated as
being fastened together;
Figure 6 is a perspective view of a skate boot sole of the
present invention;
Figure 7 is a top elevational view of the skate boot sole;
and
Figure 8 is a side elevational view of a roller hockey skate
including a skate boot of the present invention.
In the drawings, preferred embodiments of the invention are
illustrated by way of example. It is to be expressly understood
that the description and drawings are only for purposes of
illustration and as aid to understanding, and are not intended to
be a definition of the limits of the invention.
Detailed Description of Preferred Embodiments
Referring to Fig. 1, an ice hockey skate 20 is comprised of
two main elements, an skate boot 1 and a blade assembly 16. The
skate boot comprises a boot upper 6 and a sole 2. The boot upper
6 encircles the dorsal portion of the foot, the ankle, the heel
and a part of the lower portion of the calf of the skater. The
boot upper 6 may be constructed of several conventional materials
and according to a variety of conventional methods. In this
respect, the preferred material is ballistic nylon which is die
cut into variety of patterns which are stitched together to form
a whole. Holes 17 are preferably disposed in two rows along to
~192292
11
portion of the upper 6 over dorsal portion of the foot to allow
for the passage therethrough of laces (not shown) to tighten the
upper 6 to firmly secure the foot of the skater. All other
conventional boot upper adjustment mechanisms such as straps or
buckles, are within the scope of the present invention.
As shown in Figs. 2, 3, 4, and 5 the boot upper 6 includes a
curled-under portion 7 which is positioned to be in between the
sole 2 of the skate 20 and the plantar surface of the foot of the
skater when the skate 20 is in use. The curled-under portion 7
allows the boot upper 6 to be attached to the sole 2 of the skate
12. Such attachment is accomplished by the rivets 5 which attach
the blade assembly 16 to the sole 2 (described in further detail
hereinbelow) and also by glue or any other conventional adhesive.
The sole 2 includes a raised portion 10 shaped such that when the
curled-under portion 7 is attached to the sole 2 a relatively
planar surface is formed.
An insole 8 which aids in the structural reinforcement of the
skate is positioned within the boot upper 6 across the surface
opposite the planar surface of the foot of the skater. The insole
8 is constructed of any number conventional materials that are
relatively flexible, resilient, and lightweight. The insole 8 may
be formed by any conventional means including injection moulding
and die-cutting, depending on the material of which it is formed.
A liner 9 is inserted within the boot upper 6 on top of the
insole 8 (i.e. in use the liner 9 will be in between the plantar
surface of the foot of the skate and the insole 8.) The liner 9 is
present to provide for the comfort of the skater. It is preferably
constructed of a thin layer of foam which may be formed by any
conventional means.
The blade assembly 16 is constructed according to
conventional methods and comprises a blade holder 3 and a blade 4.
The blade holder 3 and blade 4 are flexible such that by exerting
force in different areas of his foot, the skater may alter the
conformation of the blade 4 and the portion thereof which contacts
the ice. The blade holder is preferably attached to the boot 1 by
219229~
12
means of rivets 5. As illustrated in Fig. 5, the rivets pass
through and secure together the blade holder 3, the sole 2 the
curled-under portion of the boot upper 7, the insole 8, and the
liner 9.
The skate 20 includes a sole 2 of the present invention. The
sole 2 is comprised of a composite material. The preferred
composite material is a bidirectional mix of acrylic thermoplastic
resin, glass and carbon fibres, such as the Novotek HW-5050
(trademark) material supplied by BioMechanical Composites (a
division of Medical Materials Corporation) of Camarillo,
California, USA. This material provides moderate stiffness
strength and durability with balanced directionality. It has
cross-woven upper and lower facesheets of carbon and glass fibres
(50%/50% mix, 0~ and 90~ orientation), with a preferred overall
thickness of 0.045 inches (1.14mm). A detailed specification of
the mechanical properties of this material appear in the table
below:
Novetek~ HW-5050 Naterial Properties
~ CA less~ .035 C~ .055 , .075 0~ ~ .105
(.89) (1-40) '~ (1.91) (2.67)
!e ...-AIt
c - .028 ~ .043 .059 . f' . 081
~r~ C l ~ .123 _ .189 _ .260 .~ .356
q ~
25~. ~
1160 ~ : 1215 ~ ~1275 ~ 1365
5160 5400 ~ 5540 ~ ~ ~ 6070
e ~ e
~. ~ :c~
'~ - 33100 ~ 22100 ~ 17000 ~ ' ~ 13200
~ 2.28 1.52 . 1.17 tl ~ ~ 0.91
2192292
13
NovetekTM HW-SOSO Material Properties
n~ .035 ~ -~ 0 ~.055 ~ ~ .075 ~ C .105
( .89) _ (1 - 40) _ h ( 1 ~ 91 ) ~( 2.67)
n
2.6 ~ ~ 2.2 ~ : ~ 1.8 ~ ~ 1.2
1.79 1.2 : 1.24 ~ 0.83
~ v r
5 ~ ..
~, 12 . 40 88 _ ~ 184
344 ~'3~ 1148 1:1 2325 ~ ~ ' 5280
1,
" ~
0 ~ 73700 ~: 57200 ~ 50000~' :: 44000
~ 5.08! .1:: 3.94 ~3.45 ,, l 3.03
. ,, ~
,f ~:
'~ ~ 3.3 2.9 ' 2.5 ' 1.9
2.28 2,~ 2.00 _, ~ 1.72 _ 1.31
I a
:a ~ ~ ~-
~ 4840 5175 1:1 5525 6000
3.33 .~ 3.57 3.80 4.13
e C~r. ~- ,
'- Cl ~ f ~
~ ~ '
b~ r~
r 33100; ~ ~: 25800~ I~C'~ 22500 ; ,~ ' 19800
~ 2.28~ ~ I . 1.783. ~ 1.55 ~ I 1.37
2192292
14
NovetekTM HW-5050 Naterial Properties
: ~ 1 9' ~ .035 ~ I .055 ~ ~ .075 ~ C .105
(.89) ~_ (1-40) ~ (1.91) ~(2.67)
r
--,
~; 5.0 1 5.0 ~ 5.0 .~ 5.0
~ 2.7 ~ 2.7 ,' 2.7 ~ 2.7
~ : ~ c.
~.. . e
l~ ' 7.2 . 7.2 , 7.2 , 7.2
7.2 . 7.2 , 7.2 ~ '~ 7.2
~ lr~ G' ~
' Ell ~ ~
( ~220 220 ~ 220 ~ 220
~ ~105 ~ 1l 105 ~ ~ 105 ~ 105
Per unit width
Based upon product of effective elastic modulus and moment of inertia.
In order to manufacture the sole 2, a sheet of base material
is die-cut to form the desired outer shape. The material is then
heated to between 350-390~F (175-200~C) in order to facilitate
moulding. It is then moulded into its final contoured shape by
subjecting it to a pressure between 5-10 pSi (35-70 kPa) for
approximately 15 seconds. Preferably, a sealing material is added
to the edge once the sole is cooled.
In the manufacture of the skate 20, the sole 2 iS bonded to
the curled-under portion 7 of the skate boot 6 via a suitable
adhesive. The insole 8 and liner 9 are then inserted within the
boot, the blade holder 3 positioned, and rivets 5 are inserted in
a conventional fashion to fasten the components together.
2192292
Referring to Fig. 8, a roller hockey skate 21 of the present
invention comprises a skate boot 1 including a composite sole 2
manufactured as described above in relation to an ice hockey
skate, a skate frame 13, a plurality of wheels mounted to the
frame on axles 15, an forward and rear attachment plates 11 and 12
respectively. The skate is assembled as described above except
that the frame 14 is positioned with respect to the boot 1 and
rivets 5 are inserted to secure all of the components together.
As an example, various boot soles for a standard men's U.S.
size 8 skate were constructed and tested to determine their
flexibility. The test procedure adopted was as follows:
(1) The heel end of the sole was fixedly secured to an edge;
(2) The intersection of the longitudinal centre-line of the sole
with the line perpendicular thereto across the widest portion
(hereinafter "the transverse line~) of the sole was located
(hereinafter "the intersection point");
(3) One end of an inflexible beam having a length of 12cm was
secured to the sole at the intersection point such that the
beam extended away from the intersection point along the
transverse line on the same side of the longitudinal centre-
line as the "arch portion" of the sole.
(4) A weight was attached to the other end of the beam, and the
angle of deflection of the beam (and thus the sole) in
response to the weight was measured. [The "Interior Flexion
90~" test.]
(5) The test was repeated with the beam positioned to extend away
from the intersection point along the transverse line on the
opposite side of the longitudinal centre-line. [The "Exterior
Flexion 90~" test.]
(6) The test was repeated with a beam of 18.5cm positioned to
extend away from the intersection point along the
longitudinal centre-line away from the heel. [The "Flexion 0~"
test.]
The results of the test are summarised in the table below:
21922~2
16
Sole Flexion Testing Data
Ortho : ~o Iso ~ Vinaf lex
0.045 " 0.045 " White
. ~' 45g 46g 94g
~e , e l:ox_c 1 . ~ ~ 5 ~ 24~ : 14~ 14
:e I:~Y' C~ 5, 25~ : 19~ : 13
::::
i~ 6~ , 9 ~ 6
~ ' Y Cl ' ~ . . ~ 32 ~ ' 23 ~ ~ ~: 25
F~ !rl ~ o~ 34~ ' 30~ :~: 25
~ 10 4 18 ~ : 12 ~
In the above table "Ortho 0.045"" refers to a sole made of
NovetekTM HW-5050 having a thickness of 0.045", similarly "Ortho
0.045"" refers a sole made of NovetekTM HW-5050 having a thickness
of 0.085". "Iso 0.045"" refers to a composite material made of the
same materials as NovetekTM HW-5050 having bidirectional fibres set
15 an angle of 45~ with respect to one another and having a thickness
of 0.045"", similarly "Iso 0.085"" refers to the same material
having a thickness of 0.085"". "Vinaflex White" refers to a sole
of the conventional thermoplastic rubber material (butadiene-
styrene). A sole of such material may be found on a "Professional
20 96" skate manufactured by Bauer Inc. of Canada.
The above description of preferred embodiments should not be
interpreted in a limiting manner since other variations,
modifications and refinements are possible within the spirit and
25 scope of the present invention. The scope of the invention is
defined in the appended claims and their equivalents.
