U.S. patent application number 10/735896 was filed with the patent office on 2005-06-16 for self-centering skate holder.
Invention is credited to Sunnen, August.
Application Number | 20050130571 10/735896 |
Document ID | / |
Family ID | 34653720 |
Filed Date | 2005-06-16 |
United States Patent
Application |
20050130571 |
Kind Code |
A1 |
Sunnen, August |
June 16, 2005 |
Self-centering skate holder
Abstract
A self-centering skate holder for clamping a skate blade from
above and below which maintains the blade at a pre-determined
height and parallelism. A handle is connected with a cable which is
taut and extends around the circumference of the upstanding
vertical member. The movements of the cable activate cam levers
which rotate cams that move a pair of jaws towards or away from
each other. The simultaneous movements of the cams ensure that the
jaws move in unison and through a similar distance allowing a skate
blade of any thickness to be clamped along the desired centerline.
In an alternative mechanism, a tie bar extends between the jaws and
is operated by a cam to induce equal and opposite movement of the
jaws.
Inventors: |
Sunnen, August; (Chatham,
CA) |
Correspondence
Address: |
BLAKE, CASSELS & GRAYDON LLP
BOX 25, COMMERCE COURT WEST
199 BAY STREET, SUITE 2800
TORONTO
ON
M5L 1A9
CA
|
Family ID: |
34653720 |
Appl. No.: |
10/735896 |
Filed: |
December 16, 2003 |
Current U.S.
Class: |
451/383 |
Current CPC
Class: |
B24B 3/003 20130101;
B24B 41/06 20130101 |
Class at
Publication: |
451/383 |
International
Class: |
B24B 019/00 |
Claims
1. A skate holder comprising a base, a mounting plate secured to
said base and having an elongated slot therein to receive a blade
of a skate, a pair of jaws located on said mounting plate on
opposite sides of said slot and moveable relative to one another to
engage opposite sides of said blades, and an operating mechanism
connected to each of said jaws and operable to move said jaws
conjointly from an open position to a closed position whereby said
jaws remain equally spaced to opposite sides of a datum during such
movement.
2. A skate holder according to claim 1 wherein said operating
mechanism is supported on said mounting plate.
3. A skate holder according to claim 2 wherein said operating
mechanism includes a flexible tensile member to transfer movement
of one of said jaws to another of said jaws.
4. A skate holder according to claim 2 wherein each of said jaws is
slidably mounted on said plate and constrained for movement in a
direction perpendicular to said slot.
5. A skate holder according to claim 4 wherein movement of said
jaws relative to said mounting plate is induced by a cam acting on
each of said jaws.
6. A skate holder according to claim 5 wherein each of said cams is
rotatably mounted on said mounting plate and engages a follower of
a respective arm of said jaws.
7. A skate holder according to claim 6 wherein each of said cams
include an operating arm and a linkage to interconnect said
operating arms.
8. A skate holder according to claim 7 wherein said linkage
includes a flexible tensile member extending from a manual operator
to selected areas of said operating arms.
9. A skate holder according to claim 8 wherein said manual operator
is connected directly to one of said operating arms.
10. A skate holder according to claim 9 wherein said tensile member
is entrained about guides disposed about said slot.
11. A skate holder according to claim 10 wherein said tensile
member is located in a recess in said mounting plate and said
guides are disposed in said recess.
12. A skate holder according to claim 3 wherein said operating
mechanism includes a tie bar that extends across said slot to
transfer a force applied to one side of said slot to the opposite
side thereof.
13. A skate holder according to claim 12 wherein said force is
applied by a cam member acting between said one side and said tie
bar.
14. A skate holder according to claim 13 wherein said cam member is
rotatably secured to one side and a follower engages said cam
member to transmit said force to said tie bar.
15. A skate holder according to claim 1 wherein said mounting plate
includes a pair of beams disposed on opposite sides of said slot
and a jaw is located on a respective on of said beams.
16. A skate holder according to claim 15 wherein said beams have a
similar stiffness in bending such that a force applied to each of
said beams produces a substantially equal deflection of each
beam.
17. A skate holder according to claim 16 wherein one of said beams
is defined between an edge of said plate and said slot and the
other of said beams is defined between said slot and a slit formed
in said mounting plate.
18. A skate holder according to claim 15 wherein said jaws are
slideably mounted on said beams and said operating mechanism cause
equal and opposite movement of said jaws relative to said slot.
19. A skate holder according to claim 15 wherein said jaws are
secured to said beams for movement therewith and said operating
mechanism induces equal and opposite deflection of said beams.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to skate holders for use with
skate sharpening machines.
DESCRIPTION OF THE PRIOR ART
[0002] Skates used in activities such as hockey, figure skating,
speed skating and for leisure include a boot and a blade. The blade
is attached to the bottom of the boot and is used to `dig into` an
ice surface allowing the skater to glide along the ice due to the
opposing force imparted on the skater when pushing against the ice
surface. To effectively grip the ice surface, the blade includes a
concave surface at its lowermost edge. This concave surface,
commonly known as a `hollow ground`, produces two parallel edges
opposed about the centreline of the hollow ground. Through repeated
contact with the ice surface, the edges are worn down due to
friction with the ice surface and periodically need to be
sharpened.
[0003] Sharpening a skate blade involves restoring the sharp edges
of the skate blade by bringing the dull edges into engagement with
the convex radius of the face of a grinding wheel and applying
pressure. This allows the grinding wheel to grind the blade in a
manner that restores the previously achieved sharp edges with two
parallel edges. A proper sharpening requires that the centreline of
the hollow grind be in a similar plane as the centreline of the
convex radius of the grinding wheel. This is achieved by
maintaining the skate blade in the proper orientation and at the
proper height.
[0004] Typically, a skate sharpening grinding wheel is horizontally
oriented so that its axis of rotation is perpendicular to the table
on which it is mounted. With the grinding wheel parallel to the
table, the skate blade must be held with its outwardly facing edges
parallel to the grinding table and the concave surface of the blade
held at an identical level as the convex radius of the grinding
wheel. To maintain this orientation, a holder is required which
typically includes a clamping mechanism to maintain the skate in
the proper position for the duration of the sharpening
procedure.
[0005] A skate holder with a clamping mechanism is shown in a U.S.
Pat. No. 4,078,337 to Chiasson et al. The skate blade is placed
with one outwardly facing surface against a stationary jaw. The
opposing jaw is lowered against the other outwardly facing surface
and tightened to secure the skate in place. The stationary jaw is
positioned so that a particular blade in the proper alignment with
the convex radius of the grinding wheel. By securing the skate
blade between a clamping jaw and a stationary jaw, any blade that
is clamped would be held at a similar level. Since the thickness of
a skate blade may vary between different skate models and different
skate types, this type of clamping mechanism does not ensure that
the centrelines of the hollow ground and convex outer radius of the
grinding wheel are aligned properly. A misaligned blade will of
course impart an uneven sharpening due to the off-center grinding
from the grinding wheel.
[0006] To ensure the centrelines of the hollow grind and convex
outer radius of the grinding wheel are properly aligned,
self-centering skate holders have been developed. To achieve
self-centering, the clamping mechanism allows both jaws to approach
the blade from their respective sides. By moving identical
distances during the clamping operation, no matter the thickness of
the blade, the centerline will be properly aligned. A
self-centering skate holder is shown in a U.S. Pat. No. 4,055,026
to Zwicker and similarly a U.S. Pat. No. 6,422,934 to Blach et al.
The clamping arms in these designs are pivoted about an axis
located a distance behind the point of clamping and consequently
behind the boot and the blade. This arrangement creates a large
area for the skate to be placed. While this design achieves
self-centering, the location of the pivot axis renders a large and
bulky apparatus. To achieve a proficient sharpening, it is
beneficial for the user to have full control of the skate holder.
The user must guide the holder towards the grinding wheel,
therefore a large and bulky design is not desired.
[0007] It is therefore an object of the present invention to
obviate or mitigate at least one of the above mentioned
disadvantages.
SUMMARY OF THE INVENTION
[0008] In one aspect a self-centering skate holder is provided
comprising a base, a mounting plate secured to said base and having
an elongated slot therein to receive a blade of a skate, a pair of
jaws located on said mounting plate on opposite sides of said slot
and moveable relative to one another to engage opposite sides of
said blades, and an operating mechanism connected to each of said
jaws and operable to move said jaws conjointly from an open
position to a closed position whereby said jaws remain equally
spaced to opposite sides of a datum during such movement.
[0009] Preferably the operating mechanism is supported on the plate
and includes a flexible tensile member to transfer movement of one
jaw to the other.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] These and other features of the preferred embodiments of the
invention will become more apparent in the following detailed
description in which reference is made to the appended drawings
wherein:
[0011] FIG. 1 is a perspective view of a skate sharpener and skate
holder;
[0012] FIG. 2 is a perspective view of the skate holder of FIG.
1.
[0013] FIG. 3 is a front view of the skate holder shown in FIG.
1;
[0014] FIG. 4 is a rear view of the skate holder shown in FIG.
1;
[0015] FIG. 5 is a section on the line IV-IV of FIG. 3;
[0016] FIG. 6 is a perspective view of components of the holder of
FIG. 2;
[0017] FIG. 7 is an exploded view of a portion of the holder of
FIG. 2;
[0018] FIG. 8 is a partial view of the upper and lower clamping
jaws moving between open end closed positions with a skate blade
disposed between.
[0019] FIG. 9 is a front view of a further embodiment of a
component used in the skate holder of FIG. 1.
[0020] FIG. 10 is a perspective view of an alternative embodiment
of a skate holder.
[0021] FIG. 11 is a view on the line XI-XI of FIG. 10.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] Referring therefore to FIG. 1, a skate sharpening apparatus
10 includes a skate holder 12 that supports a skate 14 having a
skate blade 15. The holder 12 is slideable on a work surface 18 so
as to be manoeuvrable past a grinder 16 having a grinding wheel 20.
The grinding wheel 20 is positioned to rotate about a vertical axis
in a horizontal plane and, upon engagement with the blade 15, to
grind the requisite profile.
[0023] The details of the holder 15 can be seen in more detail in
FIGS. 2 through 7. The holder 12 has a base 22. A pair of handles
26 are provided on the base 22 to facilitate manipulation of the
holder 12 on the worktop 18. A mounting block 28 is secured to an
upturned lip 24 of the base 22 by bolts 30. The position of the
mounting block 28 relative to the base is adjusted by means of set
screws 32 which are threaded into the base 22 and bear against the
underside of the mounting block 28. The set screws 32 provide a
nominal or coarse adjustment for the disposition of the mounting
block 28 relative to the base 22 to ensure alignment between the
holder 12 and the base 22.
[0024] The mounting block 28, has an open ended slot 34 at each end
in which a pair of cam members 42 are mounted. Each of the cam
members 42 are mounted on threaded pivot bolts 44 secured to the
lower edge of a mounting plate 40. The cam members 42 provide an
outer surface that is eccentric to the bolts 44 and have a radial
handle 46. The cam member 42 is dimension to be a close fit within
the slot 34 such that rotation of the cam member 42 on the bolts 44
provides relative vertical adjustment between the plate 40 and the
mounting block 28. This arrangement provides a fine alignment of
the plate 40 relative to the base 22 with the locking bolts 30
clamping plate 40 to the mounting block 28 after the required
alignment has been achieved.
[0025] The plate 40 has a planar central portion 50 and curved end
portions 52. An elongate slot 54 extends through the central
portion 50 into each of the end portions 52 and is dimensioned to
receive the blade 15 of a skate with adequate clearance to
accommodate different sizes and thicknesses. A pair of jaws 56, 58
are slideably mounted on the central portion 50 and are moveable by
an operating mechanism 60 between an open position in which the
slot 54 is relatively unencumbered and a closed potion in which the
jaws 56, 58 engage the skate blade 15. Referring again to FIGS. 4
to 7, the jaws 56, 58 each have a pair of slots 62 that receive a
guide pin 64 secured to the mounting plate 40. The guide pin 64 is
a sliding fit within the slot 62 and therefore constrains the jaws
56,58 for movement in a direction perpendicular to the axis of the
slot 54.
[0026] The upper jaw 56 has a follower recess 66 formed between the
slots 62 to receive a cam 68. The cam 68 is a close fit within the
recess 66 and is secured by a retainer 70 to an actuator spindle 72
for rotation with the spindle 72. The spindle 72 is rotatably
mounted in the support plate 40 and is secured at its opposite end
to a lever 74.
[0027] The lever 74, which forms part of the operating mechanism
60, has a cable 76 secured to it by a fastener 78 at a location
spaced from the spindle 72. The cable 76 is entrained within a
recess 77 extending around the periphery of the plate 40 by a set
of guide pulleys 80 each of which is rotatably secured to one of
the end portions 52 adjacent to corners of the guide plate 40. The
cable 76 also runs through slides 82 positioned between the pulleys
80 and jaws 56, 58 to cause the cable 76 to conform generally to
the curvature of the end portions 52. The length of cable 76 may be
adjusted by a threaded connector 79 so that the cable is taut
around the pulleys 80.
[0028] The cable 76 is attached on its lower run to a pair of
actuating arms 84, each of which is secured to respective spindles
86. The spindles 86 extend through the mounting plate 40 and are
connected to respective ones of a pair of cams 88. The cams 88 are
located within respective follower recesses 90 in the lower jaw 58,
similar to the recess 66, and the jaw 58 is retained by a retainer
92 secured to the spindle 86 to ensure the cams 88 rotate with the
spindles 86.
[0029] In operation, the mounting plate 40 is adjusted relative to
the base 22 using the mounting block 28 such that the longitudinal
axis of the slot 54, which acts as a datum, is aligned with the
plane of the grinding wheel 20 and is positioned on the center line
of the wheel 20. The skate blade 15 is then inserted into the slot
54 and the handle 74 rotated to move the jaws 56, 58 into
engagement with the blade 15. As the handle 74 is rotated, the cam
66 is likewise rotated and causes the jaw 56 to move inwardly
toward the blade 15. The movement of the handle 74 is also
transmitted through the cable 76 to each of the actuating arms 84.
The spindles 86 are thus rotated causing the cam 88 to cause a
corresponding displacement of the jaw 58 toward the blade 15. The
jaws 56, 58 are thus brought into engagement with the blade 15 so
that the blade 15 is held securely between the jaws and in
alignment with the wheel 20.
[0030] It will be apparent that the attachment points of the cable
76 to the handle 74 and the actuating arms 84 are chosen such that
an equal and opposite displacement of the jaws 56, 58 is obtained.
This ensures that the blade 15 is maintained on the center line of
the slot 54 in alignment with the wheel 20 as the jaws are moved
into the clamping position. Accordingly, different thicknesses of
blade can be accommodated without adjusting the disposition of the
slot relative to the plane of the wheel 20.
[0031] With the blade 15 secured, the base 22 can be manipulated to
bring the blade into engagement with the wheel 20 and grind the
required profile onto the edge of the blade 15. After the grinding
is complete, the handle 74 is simply rotated in the opposite
direction to release the jaws 56, 58 and permit removal of the
blade. It will be noted that the operating system 60 is contained
on the plate 40 and thus allows unencumbered access to the skate
during sharpening.
[0032] The eccentricity of the cams is selected such that, over the
typical range of blade thicknesses, the engagement between the cams
and the respective recesses is essentially self locking. Thus,
after the handle 74 is moved to bring the jaws into the clamping
position, the handle may be released and the jaws will remain
engaged with the blade.
[0033] It is found that the entrainment of the cable 76 over the
pullies ensures a free movement of the cable to ensure that
conjoint movement of the cam members is obtained. Whilst the
routing of the wire within a sheath might also be used, it is
believed that the entrainment around the pullies inhibits potential
binding with the sheath.
[0034] It will of course be appreciated that the handle 74 may be
separated from the actuation of the cam so that the handle may be
at either end of the support plate 40 and operate the cam through
an arm similar to that used on the lower jaw 58.
[0035] In certain circumstances the forces applied to the jaws 56,
58 through the operating mechanism 60 may be sufficient to deflect
the upper portion of the mounting plate 50 which in turn could
result in the blade not being exactly centered. A further
embodiment of mounting plate is shown in FIG. 9 in which like
components will be shown with like reference numerals with a suffix
a added for clarity.
[0036] Referring therefore to FIG. 9, a mounting plate 50a has a
central slot 54a and a peripheral groove 77a. It will be understood
that the operating mechanism and jaw are mounted on the mounting
plate 50a in a manner similar to that described above. Similarly,
the plate 50a may be secured to a mounting block 28a by bolts 44a
located on the lower edge of the plate 54a.
[0037] An elongate slit 100 is formed on the opposite side of the
recess 77a to the slot 54a. The slit 100 is placed above the block
28a and extends parallel to and over substantially the same length
as the slot 54a. The slit 100 is spaced from the lower edge of the
slot 54a by a distance (indicated `x`) corresponding to the spacing
of the upper edge of the slot 54a from the top edge of plate
54a.
[0038] The provision of the slit 100 and its placement relative to
the lower edge of the slot 54a provides a pair of beams 102, 104 of
substantially similar dimensions that support the operating
mechanism 60. The forces induced by the engagement of the jaws 56a,
58a with the blade are thus reacted by a similarly dimensioned
support and the deflection of each of the supports is similar.
Thus, the blade remains centered within the slot and variations in
the load supplied through the cam mechanism to the jaws will cause
equal and opposite displacement of the support portions of the
plate 50a to maintain the required alignment.
[0039] In the above embodiments shown in FIGS. 1 through 9, the
skate holder 12 may accommodate blades of different configurations
but may be either solid or with cut outs. However, a substantial
number of blades intended for ice hockey use are provided with the
central portion of the blade removed which provides the opportunity
for a simpler clumping mechanism as shown in FIGS. 10 and 11. In
the embodiment of FIGS. 10 and 11, like components will be
identified with like reference numerals with a suffix b added for
clarity.
[0040] Referring therefore to FIG. 10, the skate holder 12b has a
mounting block 28b on which is supported a mounting plate 50b. The
mounting plate 50b has an elongate slot 54b and a parallel spaced
slit 100b as described above with respect to FIG. 9. Adjustment of
the mounting plate 54b relative to the base 22b is accomplished as
described above with respect to FIGS. 1 through 8 so that the slot
54b is aligned with the datum as required.
[0041] The jaws 56b, 58b are secured to the upper and lower beams
102b, 104b by set screws 106. The jaws 56b, 58b are thus fixed to
the beams for movement with them.
[0042] The operating mechanism 60b includes a yolk 106 secured to
the upper beam 102b. The yolk has a channel 108 with a cam 66b
mounted within the channel for rotation on the pivot 72b. A handle
74b is secured to the pivot 72b to effect rotation of the cam
within the channel 108.
[0043] A follower 110 engages the surface of the cam 66b and is
supported in a bar 112. The bar 112 is slidably supported in the
yolk 106 with the terminal portion extending across the channel
108. The follower 110 is threaded into the terminal portion 114 so
that it may be adjusted relative to the cam 66b.
[0044] The lower end of the bar 112 is secured to a block 116
mounted on the beam 104b. In operation, the blade is inserted
between the jaws 56b, 58b with the bar 112 removed. The bar is then
inserted into the blocks 116 and yolk 106 and secured to the block
116. The follower 110 is then adjusted so as to be slightly clear
of the cam 66b and the handle 74b used to rotate the cam 66b within
the channel 108. The eccentricity of the cam 66b causes the bar 112
to be displaced and apply a force between the beams 102b, 104b. As
the beams have substantially identical cross section, the
deflection of each of the beams is the same and the jaws 56b, 58b
move into engagement with the blade to maintain it on the datum.
After sharpening of the blade, the cam 66b is released, the bar 112
removed and the skate removed from the slot 54b.
[0045] The arrangement shown in FIGS. 10 and 11 maintains the jaws
56b, 58b equally spaced from a datum. The mechanism 60b is
relatively robust and may readily be used where the configuration
of the blade permits the passage of the bar 112. It will also be
appreciated that the mounting plates 50b can readily be removed and
replaced with the alternative configuration of mounting plate such
as that shown in FIGS. 1 through 8 or FIG. 9 to allow a full range
of blades to be sharpened.
* * * * *