Note: Descriptions are shown in the official language in which they were submitted.
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(1 ) TITLE OF THE INVENTION
Sharpenable edge sharpening equipment
(2) CROSS REFERENCED APPLICATIONS
US 271 444
US 273 081
to US 278 237
US 1 284 091
US 4 471 951
US 4 512 112
Is (3) BACKGROUND TO THE INVENTION
In sharpening the blade of a knife or other similar equipment the acuteness of
the
sharpening angle often requires precision work. To achieve this the sharpening
edge must
be maintained at the same sharpening angle during the pertormance of a
sharpening action.
2o As the sharpening angle varies between equipment such as between knives or
scissors
chisels etc the correct sharpening angle must be selected prior to sharpening
such
equipment. The object of this invention is thus to provide a device that can
maintain the
selected sharpening angle throughout a sharpening session while enable
selection of the
desired sharpening angle prior to commencing with a sharpening action.
(4) FIELD OF THE INVENTION
This invention relates to sharpening equipment for sharpening a sharpenable
edge of
appropriate items and to a sharpening set assemblable into the sharpening
equipment.
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(5) PRIOR ART DESCRIPTION
Knife sharpening devices are known in the art. According to one arrangement a
sharpening
stone is recirpocable mounted by way of a rod to be mowed over the edge of an
article
desired to be sharpened. To accommodate various sharpening angles the device
provides a
number of reciprocating apertures spaced in series along a formation. The rod
is fitted along
the aperture that results in the sharpening angle nearest to that required.
(US 4 512 112)
(fi) SUMMARY OF THE INVENTION
to
According to the invention there is provided sharpening equipment for
sharpening a
sharpenable edge of appropriate items such as knives, scissors, chisels or the
like.
(7) BRIEF DESCRIPTION OF THE DRAWING
The invention is hereafter described, by way of example, with reference to the
accompanying drawings. In the drawings
Figure 1 shows sharpening equipment in the form of a sharpening device for
sharpening a
2o sharpenable edge as found on an appropriate item such as a knife, scissors,
a plane cutter
or the like, in side elevation as set for sharpening an item of which the
sharpenable edge is
steeply bevelled, as in the case of the blade of a knife,
Figure 2 shows the device as set according to figure 1, in plan view,
Figure 3 shows the device as set for sharpening an item with a less steeply
bevelled
sharpenable edge such as a pair of scissors, in side elevation,
Figure 4 shows the device as adapted into clamping fashion holding an
appropriate item
3o such as a chisel, in side elevation,
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Figure 5 shows the device as readjusted into sharpening a serratedly or like
edged item
such as a knife with a serrated cutting edge, in side elevation,
Figure 6 shows in detail the gripping means of the device as incorporating the
angle
adjustment facility,
Figure 7 shows the device along the view A-A in figures 1, 3 and 4,
Figure 8 shows the base of the device as fitted with upstanding sharpening
stones after
m removal of the guiding layout and the gripping means, and
Figure 9 shows a conventional serrated edge sharpening element used when the
device is
readjusted according to figure 5.
1s (8) DETAILED DESCRIPTION OF THE DRAWINGS
Referring to figures 1 to 5 of the drawings, sharpening equipment in the form
of sharpening
device, is generally indicated by reference numeral 10.
2o The device 10 comprises gripping means generally indicated by reference
numeral 12, a
sharpening means carrier in the form of sharpening element holder as provided
by a
sharpening element holding base 14 releasably holding a sharpening element in
the form of
a sharpening stone 16, a guiding layout arranged to perform a sharpening
session at a
constant sharpening angle in the form of a guiding arm as provided by a
guiding rod 18
2s mounted to reciprocate along an aperture in an adjustably mounted support
guide 20 in
parallel with the sharpening surface 16.1 of the sharpening stone 16 in
response to retaining
equal corresponding inner angles 22, and an angle adjustment facility in the
form of a
swivelling mechanism forming the connection between the rod 18 and the
gripping means
12 as provided by an connecting arm 24 extending integrally with respect to
the gripping
3c> means 12 and being swivellably connected to the leading end of the rod 18
via a disc 26
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fitted to the rod 18 via a socket 27 with the disc presenting a graduated dial
providing face
28 against which the leading end of the arm 24 sweeps dial fashion.
Referring to figures 1 to 3 and also to figure 5 the gripping means 12 is
provided a jaw
s fashion assembly 30 comprising an upper jaw 32 extending into the arm 24 and
a lower jaw
34. An item of which the cutting edge requires sharpening is gripping fashion
receivable in
the pinching zone 36 defined between the jaws 32, 34. Such item is securely so
held in
response the tightening of a tightenable element 40 engaging screw fashion
between the
jaws 32, 34. To enhance the gripping effect an adjustment element 42 situated
towards the
to rear ends of the jaws 32, 34 engages screw fashion with the jaw 32 while
urging with its
inner end against the inner wall of the jaw 34 as suitably recessed to limit
relative adjacent
movement of the jaws 32, 34. The jaws are retained apart even if not holding
an item by
means of a spring 44 fitted onto the element 40 between the jaws 32, 34. The
assembly 30
is arranged to cause its central axis 46 to pass through the pivotal point 48
between the
Is gripping means and the rod 18 in response to the suitable formation of the
connecting arm
24. Once an item is thus pinched in the zone 36 the axis 46 passes along its
cutting edge.
Referring particularly to figures 1 and 2 a knife 50 is normally held at a
relatively small inner
angle 22 to result in the one face 50.1 of its leading edge 50.2 lying flush
against the
2o sharpening surface 16.1 as its cutting edge bevelling angle is steep. As
more clearly shown
in figure 2 the knife 50 is pinched in the pinching zone along its blunt edge
50.3. When the
cutting edge bevelling angle is not so steep, as shown in the case of scissors
52 in figure 3,
the angles 22 require adjustment, as discussed below, to retain the leading
edge face 52.1
requiring sharpening in contact with the sharpening surface 16.1.
In the case where the item of which the sharpenable edge requires sharpening
carries a
shape that cannot fit the embodiment of the gripping means 12 as discussed in
figures 1 to 3
and 5, the gripping means 12 permits adaptation into forming a clamp 54 as
shown in figure
4. To achieve this the lower jaw 34 is removed by removal of the elements 40
and 42. The
so jaw 32 presents adjacent engaging apertures 56 (as seen in figure 2)
engageable by means
of wing nuts 58 used for securing a clamp formation 60 to the inner surface of
the jaw 32.
The clamp formation 60 is thus used to clamp an appropriate item, such as a
chisel 62, to
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the gripping means 12 by way of gripping it to the inner surface of the jaw
32. When so
clamped its handle 64 extends alongside the disc 26. As the leading portion of
the chisel 62
is still located in the zone which defines the pinching zone in the case of
the figures 1 to 3
embodiment the chisel 62 will still lie along an axis 66 that passes through
the pivotal point
48.
As discussed above in referring to figures 1 to 4, desired sharpening depends
on the
relevant face of the leading edge of a sharpenable item lying flush against
the sharpening
surface 16.1. To accommodate a large variety of cutting edge bevels the
guiding layout in
to conjunction with the swivelling mechanism is thus formed to accommodate an
infinite variety
of bevels within the range of the device 10. Once the sharpening angle of a
cutting edge is
established, the appropriate angle is set by pivoting the arm 24 relative to
the rod 18 around
the pivoting point 48 until the dial as defined by the end of the arm 24
ending appropriately
indicating the relevant angle on the face 28. Once this is set the arm 24 is
locked to the disc
Is 26 by means of a pinching screw 29 pinching fashion holding the arm 24 and
disc 26 at their
desired setting.
An adjustment from a setting as, for example, shown in figure 1 to that of
figure 3 or figure 4
will, however, also require re-setting of the rod 18 to retain a parallel
relationship between
2o the rod 18 and the sharpening surface 16.1 for causing the inner angles 22
to be the same
for achieving the desired sharpening effect. To this effect the guide 20 is
thus adjustably
mounted to a support formation in the form of a rail 68 and held in the
appropriate position
by means of a grub screw 70 releasably locking the guide 20 to the rail 68.
The guide 20 is
thus adjusted until the rod 18 again lies parallel to the sharpening surface
16.1, which will
2s cause the angles 22 to be the same again. To promote attainment of the
parallel
relationship, the device 10 is fitted with a correlator in the form of a
linear member as
provided by the handle portion 70.1 of the screw 70 which extends in parallel
with the
sharpening surface 16.1 once the screw 70 is fitted to the guide 20.
so Sharpening is achieved by to-and-fro movement of the sharpenable edge of
the appropriate
item over the sharpening surface 16.1 in the direction of arrow 72. This is
done by manual
displacement of the gripping means 12 while urging it to the desired extent
against the
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surface 16.1. It will be appreciated that sharpening is often desired to be
carried through by
way of uni-directional stroke. To this effect and referring to figure 7 the
rod 18 passes with
some vertical play along the aperture 74. As lateral movement of a cutting
edge over the
sharpening surface 16.1 is also often desired the aperture 74 has an oblong
horizontal
profile thus enabling lateral play of the rod 18 in the aperture 74 as well.
To permit a replacement or turning around of the sharpening stone 16 it fits
removably to the
base 14. The base 14 makes provision for filmy holding the stone 16 in
position once fitted
to thereto by means of a seat 75 into which the stone is locked via a locking
plate 77 as
io secured to the base 14 by means of a wing nut 79. The stone 16 is often
required to be
replaced during a sharpening action to pass though a procedure requiring
stones of different
grits.
In use according to the figures 1 to 4 embodiments, an object of which an edge
is desired to
is be sharpened is thus secured to the gripping means 12, the desired angle
selected on the
dial and the support guide 20 locked to the rail 68 in a rod 18 to sharpening
surtace 16.1
parallel relationship. Sharpening is achieved by desirably sweeping the
sharpenable edge
over the surface 16.1. Once the one side of the sharpenable edge has been
desirably
sharpened the gripping means 12 is simply swivelled though 180 degrees owing
to the
2o threaded engagement of the rod 18 to the disc 26 and the procedure repeated
for the
opposite side.
While the embodiments of the invention discussed with reference to figures 1
to 4 are ideal
for sharpening a sharpenable edge extending at least substantially linearly,
the sharpening
2s of a serrated, scalloped or saw toothed edge requires a separate sharpening
action. This
can in practise only be effectively achieved by displacement of the sharpening
element while
the item presenting such edge is retained stationary.
To this effect and referring to figures 5 and 9 the device 10 permits the
replacement of the
3o disc 26 and the gripping means 12 by a conventional sharpening element 76
for use in
conjunction with not-linear edges, as shown in more detail in figure 9.
Disengagement is
achieved by the leading end of the rod 18 fitting screw fashion into the
socket 27 fast with
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the disc 26. The sharpening element 76 is fitted with a socket by means of
which it engages
screw fashion with the rod 18. To bring the item of which the non-linear edge
requires
sharpening into a sharpening relationship with the element 76 it is again
gripped in the
pinching zone 36 of the gripping means 12 as now fitted to the bottom end of
the rail 68. The
s rail 68 is thus releasably secured to the base 14 by being screw fashion
received in a
threaded socket in the base 14 and so locked by means of a wing nut 80. An
indication of
the sharpening angle is achieved by the rail 68 presenting graduated markings
82 that
indicate the sharpening angle 84 for as long as the gripping means 12 extends
transverse to
the rail 68. As the rod 18 in this case does not reciprocate transverse to the
rail 68, the
io guide 20 provides a desiredly shaped aperture 84, as shown in figure 7 in a
wing 20.1 which
has an oblong shape in the direction of the rail 68 while also permitting
lateral play to attend
to adjacent serrations or the like.
While specialised sharpening by means of the device 10 is often only required
at spaced
is intervals, regular touching up is often required when, for example, a knife
is used in an
ongoing fashion. To this effect and referring to figure 8 the base 14 is
fitted with spaced
threaded apertures (not shown) into which conventional sharpening stones 86
are
receivable after removal of the guiding layout and the gripping means 12.
2o While the invention deals with a device 10 which is constituted from
various members the
invention also extends to a set constituting the gripping means 12 as fitted
with the disc 26,
the holding base 14, a sharpening stone 16, the guiding rod 18, the support
20, the rail 68.
The set can also include the sharpening element 76 and the sharpening stones
86.
