Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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ICE SKATE<. BLADE
FIELD OF THE INVENTION
The present invention relates to the design of ice skate blades and methods of
grinding such blades.
BACKGROUND OF THE INVENTION
In winter sports such as ice skating and hockey the blades of an ice skate are
the
point of contact for all of the forces generated in turns, spins, jumps,
stops, gathering
speed etc. Ice skates typically have a convex shape along a length of the
skate blade and a
concave shape across the width of the blade, defining two edges along the
lengthwise
edges of the blade. A skater can use either of these two edges in executing
maneuvers on
the ice surface.
With time the profiling of ice skates has evolved as former recreational
sports such
as skating evolved into Olympic sports with multiple disciplines including
long-track
speed skating, short-track speed skating, ice dance, ice etc and "shinny"
hockey on frozen
ponds, lakes, and rivers became a multi-billion dollar sporting franchise
globally with
individual players being remunerated in contracts of tens of millions of
dollars. Alongside
multiple equipment manufacturers jostle for an edge in the sports equipment
market for
the over 1.5 million registered hockey players globally and tens of millions
of skaters
globally who spend anything up to $1,000 on a pair of skates to keep up with
their heroes,
given the winning edge, etc.
As such ice skate blade profiles have evolved into a science with different
profiles
of blade between speed skating and ice dance, defender, goalie, attacker,
short speed and
long speed. Additionally atop these differences that science is establishing
from research
are the individualities of the various players and the intuitive, difficult to
quantify "feel" of
their skates. However, despite this the overall fundamental design of an ice
skate blade has
remained essentially unchanged remaining as outlined above a single concave
lateral
profile on the bottom of the blade with an essentially longitudinally convex
profile.
This design, despite significant research expenditure by the major equipment
manufacturers of ice skates and ice skate sharpening equipment, is limiting as
the single
blade provides trade-off between a single hollow with a small surface area for
gliding and
two edges for providing traction in maneuvering. Speed skates, as opposed to
hockey
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skates, for example have much longer blades and hollows for the express
purpose of
increasing the surface area in contact with the ice. Hence, after several
hundred years ice
skate blades have progressed more in recent years from refinements in
materials and
preparation, with grinding and now multiple polishing steps, with changes to
profile
occurring incrementally over the years allowing the skate to evolve to its
current design
and construction of a skate boot, a single skate blade holder, and a single
skate blade with
a single hollow which are, however, essentially the same as the original
design.
Within the prior art several approaches to adapting the design of ice skates
have
been presented. These include K. Hall in US Patent 4,907,813 entitled "Ice
Hockey Skate
Blade" wherein there is taught a skate design comprising a top edge, a skating
edge, and a
toe portion. The skating edge has a gliding portion behind the toe portion
which has a
width less than the top edge of the blade and the toe portion of the blade.
The front toe
portion of the blade allows contact with the ice and has a width equivalent to
standard
hockey ice skate widths, while the gliding portion of the blade behind the toe
section has a
narrower width corresponding to ice skate racing blades. In contrast J. Swande
in US
Patent 5,826,890 entitled "Ice Skate Blade" teaches to a blade cross-section
that varies
between a central portion and the front and rear edges. Swande identifies a
limitation in
adapting the blade design to the requirements of defensive hockey players who
favor
shorter central gliding sections to obtain better turning ability unlike
attacking hockey
players who longer central sections for increased acceleration and gliding.
Accordingly
Swande teaches to introducing a main central runner and lateral side runners
to reduce the
surface pressure applied so as to limit the depth the blade bites into the ice
wherein deep
biting is undesirable. Accordingly Swande teaches to a three-section lateral
profile that
varies from having a central section with the resultant four blade edges on a
substantially
common level to front and rear sections of the blade where the outer blade
edges are set to
a higher level than the central pair. The blade design of Swande being
symmetric along the
blade centre line at all points. The prior art of Swande is discussed below in
respect of
Figure 3.
H. Redmond et al in US Patent 4,392,658 describes a similar structure to
Swande
in some embodiments with the concept of a central blade having two edge
portions and a
flat portion such that the central portion is in contact with the ice during
gliding but the
raised side portions are engaged during turning as they are disposed
vertically away from
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the flat portion and thence are not in contact during gliding. As evident from
Figure 3
described below Redmond teaches to an essentially continuous series of designs
between
those addressing speed through to those for maneuverability.
Ilowever, these prior art designs suffered two drawbacks, first being that
they do
not address the fact that the current blade and hollow configuration was
designed to create
a turning and gliding surface with specific properties. Second, no
corresponding method of
sharpening them was developed which impacted their deployment as they are not
compatible with the standard skate machining systems that operate with a
profile grinding
wheel. It has been determined that the current skate blade configuration
generates friction
between the blade and the ice, which creates a film of water between the blade
and the ice,
the film provides for the gliding properties of the blade. The proposed
invention, by
utilizing multiple hollows creates increased blade friction and thereby
increases the water
film for gliding and will therefore increase the gliding performance of the
blade without
compromising the turning capability which has already been designed into the
current
blade configuration whilst providing for both asymmetric variations of the
blade and
variations of the blade profile along the blade. Additionally the designs are
compatible
with a new grinding system that accommodates complex profiles which may be
unique
even to a specific pair of ice skates for an individual.
It is, therefore, desirable to provide increased ice skate performance by
reducing
drag and contact friction as well as providing improved flexibility in varying
the profile of
the ice skate along its length between toe, middle and heel. It is also
desirable to provide a
means of sharpening such skates which are incompatible to existing skate
sharpening
machines.
SUMMARY OF THE INVENTION
It is an object of the present invention to obviate or mitigate at least one
disadvantage of the prior art.
In accordance with an embodiment of the invention there is provided an ice
skate
blade comprising:
a first profile formed longitudinally along a predetermined portion of the ice
skate
blade designed primarily for gliding upon an ice surface, the first profile
having an edge at
each end of the profile; and
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a second profile formed longitudinally along a predetermined portion of the
ice
skate blade designed primarily for edging into the surface, the second profile
having an
edge at each end of the profile; wherein
the first and second profiles share a common edge.
In accordance with an embodiment of the invention there is provided a method
comprising:
providing an ice skate blade formed from a predetermined composition of
materials;
forming a first profile longitudinally along a predetermined portion of the
ice skate
blade primarily for gliding upon an ice surface, the first profile having an
edge at each end
of the profile; and
forming a second profile formed longitudinally along a predetermined portion
of
the ice skate blade primarily for edging into the surface, the second profile
having an edge
at each end of the profile; wherein
the first and second profiles share a common edge.
In accordance with an embodiment of the invention there is provided a method
comprising:
providing an ice skate blade formed from a predetermined composition of
materials;
grinding a first profile longitudinally along a predetermined portion of the
ice skate
blade primarily for gliding upon an ice surface, the first profile having an
edge at each end
of the profile and ground with a first tool having width substantially less
than that of the
lateral width of the first profile; and
forming a second profile formed longitudinally along a predetermined portion
of
the ice skate blade primarily for edging into the surface, the second profile
having an edge
at each end of the profile and ground with a second tool having width
substantially less
than that of the lateral width of the first profile; wherein
the first and second profiles share a common edge.
Other aspects and features of the present invention will become apparent to
those
ordinarily skilled in the art upon review of the following description of
specific
embodiments of the invention in conjunction with the accompanying figures.
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BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the present invention will now be described, by way of example
only, with reference to the attached Figures, wherein:
Figure 1 depicts ice skate blade profiles typically employed within sports and
recreational environments and how these vary for different aspects of the same
sport for
professionals and serious amateurs;
Figure 2 depicts ice skates and the sections now considered for a skate with
varying profile for each according to the users sport;
Figure 3 depicts ice skate blade profiles according to the prior art of Swande
(US
Patent 5,826,890) and Redmond (US Patent 4,392,658);
Figure 4 depicts ice skate blade profiles according to embodiments of the
invention;
Figure 5 depicts a plan view of skate sharpening system according to an
embodiment of the invention;
Figure 6 depicts a side elevation view of the skate sharpening system
according to
an embodiment of the invention;
Figure 7 depicts the prior art approach to dressing a grinding disc of the
prior art as
well as embodiments of the invention for grinding blades according to
embodiments of the
invention; and
Figure 8 depicts a side elevation view of a skate sharpening system according
to an
embodiment of the invention for sharpening both blades simultaneously.
DETAILEI) DESCRIPTION
The present invention is directed to ice skate blades and methods of grinding
such
blades.
Reference may be made below to specific elements, numbered in accordance with
the attached figures. The discussion below should be taken to be exemplary in
nature, and
not as limiting of the scope of the present invention. The scope of the
present invention is
defined in the claims, and should not be considered as limited by the
implementation
details described below, which as one skilled in the art will appreciate, can
be modified by
replacing elements with equivalent functional elements.
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Figure 1 depicts ice skate blade profiles, circular arc 110 (CA), flat bottom
circular
are (FBC) 120, and flat bottom "V" 120 (FBV), typically employed within sports
and
recreational environments and how these vary for different aspects of the same
sport for
professionals and serious amateurs. Considering initially CA 110 then this
represents the
traditional profile of a skate. This is because the traditional method of
shaping the grinding
wheel that is used to sharpen the skate blade is to swing a single point
diamond tool in an
arc about the centerline of the grinding wheel. The variables in this CA 110
profile are the
width of the skate blade (w), the radius of the circular are (r), the included
angle at the
edge of the blade (~) and hmax the maximum depth of the groove.
The geometry shown in CA 110 is with the circular arc centered with the blade,
considered to be the best arrangement, and is known as "edges even condition".
The
interrelation between the variables can be determined from Equations (1) and
(2) below.
hõ ax = r(1- cos(a sin(w/2r))) (1)
0 = 90 - a sin(w/2r) (2)
There are two variables that can be changed in the above equations; namely,
the
width of the skate blade, w, and the radius of the groove, r. The width of the
blade, w, is
dependent upon the type of skating being done, with the typical hockey blade
being 0.110
inches (2.8 mm) wide. The typical radius, r, used by hockey players varies
from 0.250
(6.35 mm), such as shown by profile 140B for sharper turns but making gaining
speed
harder, to 2.00 (50.8 mm) inches, such as shown profile 140A making turns
difficult but
gaining speed easier.. A common radius being 0.50 (12.70 mm) inches to provide
a trade-
off between these demands from the skater. Typical values of groove radius, r,
when
applied to hockey skates, 0.110 inches (2.8 mm) wide, will give the values of
maximum
depth, h-õax, and the edge angle as shown below in Table 1.
Radius, r (in) Depth, h (in) Edge Angle, (deg)
0.250 0.00613 77.29
0.500 0.00303 83.68
0.750 0.00202 85.79
1.000 0.00151 86.85
1.250 0.00121 87.48
1.500 0.00101 87.90
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1.750 0.00086 88.12
2.000 0.00076 88.420
Table 1: Typical Circular Arc Blade Parameters for Hockey
It is worth noting that the range of edge angles, 4), and depths, h, is very
limited. It
is common knowledge in the ice skating world that a smaller radius provides
better turning
ability along with a slower glide speed, while a larger radius provides
superior glide
speeds along with poorer turning ability.
Now considering the FBC 120 then the cross-section through an ice skate blade
is
shown where a flat bottom has been added to the traditional circular arc
profile, leaving
the two interior circular arc profiles. In this case, the edge angle, c), will
remain the same
as those calculated for circular arc profiles of various radii, r, as shown in
Table 1 above
but the depth of the flat, h, will be adjustable to any value less than the
maximum depth,
hmax, under the blade as calculated for the circular arc. The depth of the
flat, h is the
distance between a line joining the two blade edges, and the flat bottom of
the skate blade.
The width of the flat bottom, d, is given by Equation (3) below.
d =2r2 - (r- hf ax + h)2 ]l/2
(3)
The advantage of this profile over the traditional circular arc profile is
that the edge
angle, 4), can be maintained while the depth, h, of the profile is reduced
from, hmax ,
leading to a potentially faster skate with less drag. A nomenclature for FBC
profiles used
by some manufacturers is FBC-XXX-YY where XXX is the radius, r, of the
circular arc in
thousandths of an inch and YY is the depth of the flat, Ii, in thousandths of
an inch.
Now referring to FBV 130 then this groove profile on an ice skate blade is an
attempt to overcome the primary shortcoming of the traditional circular arc
profile; the
fact that the edge angle, 4, and the maximum depth of the groove, h,,,ax, are
linked. This
is a major constraint of the CA 110 profile. This profile is named flat bottom
`v' (FBV) as
the two lower internal profile lines would intersect in a V if there were
projected, and the
bottom of the ice skate blade forms a flat bottom for the V shape resulting
from that
projection. There are a few geometric properties that define the shape of the
FBV 130 ice
skate blade profile; the blade width, w, the width of the flat bottom, d, and
the depth of the
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flat bottom, h. The height under the blade, h, is the distance between a line
joining the two
blade edges and the flat bottom. The edge angle, 4), at the blade edge, in the
case of a
symmetrical (central to the blade width) location of the blade bottom is given
by Equation
(4) below.
0=atan(w-d)/2h (4)
As can be seen from this formula; once a blade width, w, is known, a value of
blade bottom width, d, can be chosen in conjunction with the depth of the
flat, h, to obtain
a wide range of edge angle, 4), values. A similar nomenclature as that for FBC
120 is used
by some manufacturers, being FBV-XXX-YY, where XXX represents the width of the
flat
bottom, in thousandths of an inch, and YY represents the flat depth, h, in
thousandths of
an inch.
The ability to vary the blade profile being shown by profiles 150A through
150D
whereby moving from first profile 150A to second profile 150B are variations
for constant
bottom width, d, but varying depth of flat, h, giving better turns. Moving
from first profile
150A to third profile 150C is decreasing bottom width, d, for constant depth
of flat, h,
giving more speed. Moving diagonally from first profile 150A to fourth profile
150D is
decreasing bottom width, d, and increasing depth of flat, h, trying to balance
speed and
turning.
Referring to Figure 2 there are depicted hockey skate 210 and figure skate 220
showing the differences in design not only of the boot but the blade fitting
to the boot and
the construction of the blade. Historically a blade was a blade but now
sharpening may
consider the blade as having four zones, toe 212, front 214, middle 216 and
heel 218
which are potentially profiled differently one zone from another but may also
vary in
profile between say a defenseman, an attacker, and a goalie for ice hockey.
Balancing the
designs of these zones results in improved balance, sharper turns, quicker
turns, increased
acceleration, reduced fatigue, increased power in strides and improved
gliding, injury
reduction, increased agility, increased lateral movement, increased speed,
increased
stability, and controlled leg extensions. However, providing such options to
the general
public as opposed to professional sportsmen and sports women has hitherto been
unfeasible through the design of the blades supplied generally on commercial
hockey
skates, one design for all, and skate sharpening machines.
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Considering these zones then the toe 212 generally is used for starts,
acceleration,
and final toe snap and may represent 1 second of a stride when this zone is in
contact with
the ice. The front 214 is primarily used for acceleration and ankle dekes and
typically
represents 1-3 second of stride movement. The middle 216 is used most for
gliding,
stopping, forward strides of several seconds, and provides balance and pivot
point in
motion. Finally the heel 218 is used in stop-turns, extension and backward
pushes for
backward skating as well as crossovers, direction changes and balance.
Typically the toe
212 and heel 214 represent 20% of the blade length, the middle 216 60%, and
the heel 218
20%.
Referring to Figure 3 there is depicted ice skate 310 according to the prior
art of
Swande in US Patent 5,826,890 entitled "Ice Skate Blade" comprising front 301,
middle
302, and rear 303. Running continuously from the front 301 to the rear 303 is
middle
element 304 that has on either side runners 305 that varies in profile such
that in the front
301 and rear 303 the lower surface of the side runners 305 is disposed away
from the ice
surface when the ice skate is disposed in an upright position. However the
profile of the
side runners 305 in the middle 302 is such that they have the same vertical
position as the
middle element. As such the ice skate 310 has symmetrically disposed side
runners 305
that may be formed either in the same one piece as the middle 304 or formed by
different
elements.
Also shown in Figure 3 are first to third schematics 350A to 350C respectively
according to the prior art of Swande in US Patent 5,570,893 entitled "Blade of
an Ice
Skate" having a blade 321 with central portion 322 that has disposed on each
side a first
side runner 323 and second side runner 324. In first schematic 320A the blade
321 is
shown in upright position such as during gliding wherein the central portion
322 is in
contact with the ice. In second schematic 320B the blade 321 is shown leaning
over to a
first predetermined degree wherein the first side runner 323 is now in contact
with the ice
as opposed to just a single edge as with a typical prior art blade such as FCA
110 or FBV
130 in Figure I supra. Now referring to third schematic 320C the blade 321 is
shown
leaning over to a second predetermined degree wherein the second side runner
324 is now
in contact with the ice. As such Swande teaching to a blade offering enhanced
gliding
whilst the skater is turning, such as for example would be beneficial in speed
skating.
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In first profile 331 through sixth profile 336 blade geometries according to
the
prior art of Redmond in US Patent 4,392,658 entitled "Skate Blade" which have
first and
second longitudinal extending edges upwardly and inwardly rising from the
outermost
cutting edges together with longitudinal extending middle face centrally
disposed between
these edge faces. The progression of first profile 331 to sixth profile 336
evolving from
essentially a FBV 130 design through to a design such as comparable to the
front 301 of
Swanke in ice skate 310 wherein the central portion is in contact with ice in
the upright
position and the side runners are not in contact.
Referring to Figure 4 there are shown exemplary blade cross-sections according
to
embodiments of the invention. First blade cross-section 410 depicts a pair of
circular arc
profiles applied to the bottom of the skate providing increased friction
allowing improved
gliding performance. Second blade cross-section 420 comprises first circular
section
420A, flat-bottomed V 420B, and second circular section 420C. Similarly third
blade
cross-section 430 comprises first circular section 430A, flat-bottomed V 430B,
and second
circular section 430C but differs from second blade cross-section 420 in that
first and
second circular sections 430A and 430C respectively are identical whereas they
are
different in second cross-section 420. Finally in fourth blade cross-section
the blade
profile comprises vee-groove 440A and circular groove 440B. Each of the blade
cross-
sections in Figure 4 provides a balancing between gliding characteristics,
e.g. by the vee-
groove 440A in fourth blade cross-section 440, and maneuvering e.g. by the
circular
groove 440B
It would be apparent to one of skill in the art that these profiles many be
adapted
according to the left or right skate of the user. Accordingly there is shown
fifth blade
cross-section 450 which is the mirror image of fourth blade cross-section 440,
and hence
representing for example the left skate of the user wherein fourth blade cross-
section
represents the right skate of the user. Depending upon the characteristics of
the user in
terms of weight, skating profile, position, etc then the left and right skate
blades may not
be mirror images of one another but different in terms of number of profile
sections, depth
of each profile section, type of profile section (e.g. FCA, FBV etc) .
Similarly the profile
on different sections of the skate such as described above in respect of
hockey skate 210
may be different, for example the front 214 and heel 218 may be designed
primarily for
biting into the snow for stopping, accelerating, and maneuvering. Middle 216
may be
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designed for gliding only or vary along its length according to the users
balance etc for
gliding weight to the front and maneuvering at the rear for example.
Accordingly a profile as taught provides for a first profile formed
longitudinally
along a predetermined portion of one side of a blade designed for gliding upon
an ice
surface with two edges, a second profile formed longitudinally on the opposite
side of the
blade in the same predetermined portion designed for edging into said ice
surface with two
edges, where the first and second profiles share a common edge. It would be
evident to
one skilled in the art that alternatively the blade may be formed from
multiple discrete
blades, each with one of the profile segments of the final blade. Optionally
such multiple
discrete blades may be formed from different materials and the edges may be
treated
differently, for example different anneals or surface finishes.
Whilst considering the design of an ice skate blade it is important to also
consider
how that ice skate blade will be sharpened as with use the sharp edges become
dulled and
blunt so that optimum performance is only achieved after the blade is re-
sharpened. At
present commercial blade sharpening systems employ a pre-formed grinding wheel
that
has a predetermined profile. This profile is therefore applied to the entire
length of the
blade. Accordingly if a user wishes to have a different profile at the middle
and heel of a
skate blade that already presents a significant issue to the operator of the
grinding
machine. Now consider a profile that varies from say an FCA on the toe to a
symmetric
dual FBV at the middle to a dual FCA / FBV profile such as shown in third
blade cross-
section 430 of Figure 4. Then the next pair of skates is asymmetric dual FCA /
FBV such
as shown in second blade cross-section 420 of Figure 4.
Clearly such profiles are incompatible with prior art skate sharpening systems
unless multiple grinding wheels with the different profiles are stocked and
changed several
times per skate blade sharpened. Accordingly such difficulties have limited
the evolution
of ice skate blade profiles as they cannot be re-sharpened such that perhaps
high profile
speed skaters, figure skaters, and hockey players may pay for a quantity of
blades that are
essentially use once and thrown away or skate sharpening machine manufacturers
are
willing to invest time supporting these high profile athletes as part of their
marketing
activities. But that is not representative of the vast majority of skaters who
would benefit
from enhanced ice skate profiles even if they were more limited to perhaps a
small number
for defenseman, several for attackers, some for goaltenders etc as well as
profiles that are
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tailored to novices as well as experts. As such it would be beneficial to
provide a highly
flexible ice skate blade sharpening system that allows complex geometries to
be ground
and polished as well as providing high flexibility to account for substantial
variations
between sequential skates being sharpened.
Now referring to Figure 5 there is depicted a plan view of a skate sharpening
system 500 according to an embodiment of the invention. A skate comprising
skate body
510A and blade 510E is mounted to a holder 540 which is itself mounted to
first stage 590
and therein to the base 530 of the skate sharpening system 500. The second
portion of the
skate sharpening system 500 being a grinding wheel 550 that is mounted to a
frame 585
which includes a drive mechanism, not shown for clarity, for the grinding
wheel 550
which may be for example direct drive or differentially driven according to
the degree of
control / complexity of the skate sharpening system 500. This frame 585 is
mounted to a
second stage 580 and therein to the base 530 of the skate sharpening system
500. The
frame 585 including adjustment screw 560 which is driven by drive 570.
Adjustment
screw 570 and corresponding drive 570 may be provided for example for multiple
axes of
the system including lateral, translational, vertical, yaw, pitch and roll.
According to one embodiment of the invention drive 570 may be manually
adjusted, second stage 580 rigidly mounting the frame 585 to the base 530 and
first stage
590 be manually controlled. According to another embodiment of the invention
the first
stage 590, second stage 580 and drive 570 may all be controlled through a
central
microprocessor to automate the process of grinding a desired profile thereby
improving
the reproducibility of the profile applied to the blade 510B. It would be
evident to one
skilled in the art that the programme may be varied allowing an operator to
simply key in
an identity of a skater for example to retrieve their custom profile and
reapply this to the
skates.
It would also be evident to one of skill in the art that in both manual and
automatic
approaches that a measurement and indication of pressure between the blade
510B and
grinding wheel 550 may be made / displayed allowing increased control of the
grinding
process. Optionally if a conductive grinding wheel 550 is employed then an
electrical
contact may be made to both the grinding wheel 550 and blade 510B such that
initial
contact of the blade 510B to the grinding wheel 550 can be detected or
monitored to detect
errors in position as contact is lost for example.
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Now referring to Figure 6 there is shown a side view of a skate sharpening
system
600 according to an embodiment of the invention, such as skate sharpening
system 500 as
described in Figure 5 for example. The skate sharpening system 600 comprising
a skate
sub-system and grinding sub-system 600B. As shown a skate boot 630 is mounted
into a
holder 610 forming part of the skate sub-system, the holder 610 being mounted
to a first
stage 620. The skate boot 630 being clamped in the holder 610 through the
action of a
clamp engaged through operating lever 615. Attached to the skate boot 630 is
skate blade
640.
Grinding sub-system 600B comprises a grinding disc 685 that is mounted to a
mounting plate 680 and thereby to spindle 670 which is driven by drive belt
660 from a
motor, not shown for clarity. These elements being mounted to drive sub-frame
650 which
is mounted to second stage 655. First stage 620 provides motion longitudinally
with
respect to the skate blade 640, i.e. along an axis perpendicular to the plan
of the side view.
Second stage 665 provides motion both in a linear axis perpendicular to the
axis of motion
of first stage 620, i.e. across the width of the skate blade 640, and
rotational motion about
a point "P" that is established as being at a point representing the expected
interface
between the grinding disc 685 and skate blade 640. As such the combined action
of first
stage 620 and second stage 665 is to provide four axis of movement between the
skate
blade 640 and grinding disc 685 allowing the grinding disc 685 to follow
complex
surfaces of movement such as those necessary to implement the profiles
according to
embodiments of the invention such as first to fifth blade cross-sections 41.0
through 450
respectively in Figure 4.
Referring to Figure 7 there is shown a first schematic 700A of a prior art
approach
to dressing a grinding disc and profiling a skate blade. A template 710 is
initially provided
that has a profile formed with a hard surface, e.g. CVD diamond that has in
the middle a
FBV profile. This template 710 is used to dress a grinding wheel 720 by
grinding the
grinding wheel 720 against the template 710. Once dressed the grinding wheel
720 can
then be used to grind the FBV profile onto a blade 730. Accordingly in order
to adjust a
blade profile either the grinding wheel 720 should be replaced, and dressed
with another
template 710, or the same grinding wheel 720 redressed with the new template
710. As
such changing the profile for each user and as such each sequential pair of
skates is a time
consuming process. Also adjusting the profile between the different parts of
the blade 730,
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CA 02757439 2011-11-02
such as toe 212, front 214, middle 216, and heel 218 as shown in Figure 2
above, would be
extremely difficult even though it is beneficial for professional skaters and
amateurs in
competitions etc.
Second and third schematics 700B and 700C depict sharpening a skate blade
according to embodiments of the invention. Second schematic 700B depicts a
dual FBV
profile 750 on a skate blade that is ground and / or polished with thin
profile blade 740.
Third schematic 700C depicts a FCA / FBV blade 790 along with first through
third blades
760 to 780 respectively. These blades providing different grinding profiles
which may be
employed along with thin profile blade 740 alone or in combination with a
skate
sharpening system such as described supra in respect of skate sharpening
systems 600 and
700 in Figures 6 and 7 respectively. It would be apparent to one skilled in
the art that first
and second stages 620 and 665 may be controlled through the use of a
microprocessor to
execute the complex sequence of movements required to control the blade in
order to
provide the profiles for ice skate blades according to embodiments of the
invention. As
such a skate sharpening system according to an embodiment of the invention
allows for an
operator of the system to program a new blade profile into the system and have
it executed
automatically. Hence, when a new pair of skates are loaded all the operator
has to do is
execute a new program or if the skates are for the same users as the previous
pair repeat
the currently loaded program. It would be evident to one of skill in the art
that such a
combination of thin grinding elements and automated skate sharpening system
allows for a
flexibility in profiling skate blades that cannot be achieved with the
existing systems of the
prior art.
It would also be evident to one of skill in the art that in skate sharpening
systems
600 and 700 that a measurement and indication of pressure between the blade
and grinding
wheel may be made / displayed / utilized allowing increased control of the
grinding
process. Optionally if a conductive grinding wheel is employed then an
electrical contact
may be made to both the grinding wheel and blade such that initial contact of
the blade to
the grinding wheel can be detected or monitored to detect errors in position
as contact is
lost for example.
Now referring to Figure 8 there is depicted a skate sharpening system 800
according to an embodiment of the invention wherein a pair of sharpening sub-
systems,
for example skate sharpening system 600 of Figure 6 are assembled to a base,
not shown
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CA 02757439 2011-11-02
for clarity. As such a skate mount 800A engages first and second grinders 800B
and 800C.
Each of the first and second grinders consists of a grinding wheel 830 that is
driven
through a belt system 845 from a motor, not shown for clarity, which provides
the
rotational power for the grinding wheel 830. This drive and wheel sub-assembly
is
mounted to a body 820 that is in turn mounted to a stage 810.
The skate mount 800A provides for mounting of left skate 850A and right skate
850B with corresponding left blade 840A and right blade 840B with each being
clamped
via a levered mechanism engaged via first and second handles 860A and 860b
respectively. Skate mount 800A further comprising skate stage 870. As with
skate
sharpening system 600 in Figure 6 each stage 810 and skate stage 870 may be
fixed or
adjustable relative to the base and may be manually or mechanically
positioned. It would
therefore be evident to one skilled in the art that the profile applied from
first grinder 800B
to left blade 840A may be the same or different to that applied by second
grinder 800C to
right blade 840B.
It would be evident to one skilled in the art that whilst the simplest design
is the
stacking of a pair of skate sharpening systems 600 to form skate sharpening
system 800
that under appropriate computer control the relative motions of first and
second grinders
800B and 800C may be controlled such that they operate without requiring a
minimum
complete clear separation between them such that the vertical height of the
skate
sharpening system 800 may be reduced. Accordingly skate sharpening system 800
can
provide complex blade profiles to each of the left and right skates of a user
with accurate
cross-referencing of the profile of one blade to the other.
It would be evident to one skilled in the art that the ice skate blade may be
formed
from a variety of materials according to the cost, strength, weight, rigidity,
and
performance tradeoffs that the skate manufacturer is working within. Such
blades may for
example be formed from carbon steel, high strength low alloy steel, low alloy
steel,
stainless steel, as well as metals such as titanium. Alternatively blades may
be formed
from a variety of composite materials which are engineered materials that
comprise two or
more components including for example polymer composites that combine
reinforcing
fibers such as carbon fiber, glass fiber, basalt fibers, or other reinforcing
fibers with a
thermosetting or thermoplastic polymer resin such as epoxy, nylon, polyester,
polypropylene, or other resins wherein the reinforcing fibers provide
stiffness and strength
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in the direction of the fiber length, and the resin provides shape and
toughness and
transfers load between and among the fibers. Optionally, the blades may be
formed from
one or more ceramic materials including for example oxides such as alumina,
beryllia,
ceria, and zirconia; non-oxides such as carbides, borides, nitrides, and
silicides; as well as
ceramic composite materials including for example particulate reinforced,
fiber reinforced,
and combinations of oxides and non-oxides.
The above-described embodiments of the present invention are intended to be
examples only. Alterations, modifications and variations may be effected to
the particular
embodiments by those of skill in the art without departing from the scope of
the invention,
which is defined solely by the claims appended hereto.
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