KNIFE SHARPENING STEEL

AFFUTE-COUTEAUX

English Abstract

An improved sharpening steel is disclosed adapted for a manual
sharpening of the cutting edge of a knife blade which is held by a
blade sharpening angle guide having bearing side faces, with the
cutting edge extending a distance outside the guide for being
sharpened at a proper angle. The sharpening steel comprises a rough
sharpening surface and an additional smooth guiding surface.
Instead of the rough sharpening surface of the sharpening steel,
the additional smooth guiding surface is provided for contacting
the bearing side faces of the guide while the blade cutting edge
being sharpened by the rough sharpening surface of the steel when
the knife blade and blade sharpening angle guide combination are
drawn across the sharpening steel. Therefore, the wearing away of
the blade sharpening angle guide is avoided.

Claims

The embodiments of the invention in which an exclusive
property or privilege is claimed are as follows:
1. A sharpening steel adapted for a manual sharpening of a
cutting edge of a knife blade which is held by a blade sharpening
angle guide having two bearing side faces with the blade cutting
edge extending a distance outside the blade sharpening angle guide
for being sharpened at a proper angle, comprising:
an elongated steel body having two ends;
a handle mounted on one of the ends of the steel body;
the steel body having a sharpening portion formed with a
sharpening surface and a guiding portion formed with a smooth
guiding surface which has a longitudinal length not less than a
width of the bearing side faces of the guide, the sharpening
surface contacting the blade cutting edge while the guiding surface
contacting one of the two bearing side faces of the blade
sharpening angle guide when the knife blade and the sharpening
angle guide combination are drawn across the sharpening steel.
2. A sharpening steel according to claim 1 wherein the
elongated body is a steel rod.
3. A sharpening steel according to claim 2 wherein the steel
rod is substantially equally divided by the sharpening portion and
guiding portion.
4. A sharpening steel according to claim 2 or 3 wherein the
guiding portion is between the sharpening portion and the end on
which the handle is mounted.
5. A sharpening steel according to claim 4 wherein the
sharpening portion and guiding portion have substantially a equal
diameter.
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Description

213~
Field of The Invention
The present invention relates to a sharpening device and
particular to a sharpening steel for a manual sharpening of the
cutting edge of a knife blade which is held by a blade sharpening
angle guide having two bearing side faces with the cutting edge
extending a distance outside the guide for being sharpened at a
proper angle.
Background of The Invention
It is common to use a sharpening steel for a manual sharpening
of the cutting edge of a knife blade. A conventional sharpening
steel generally comprises a steel rod formed with a sharpening
surface substantially along the whole length of the steel rod and
with a handle mounted on one of the ends thereof.
It is also known in the prior art to use a blade sharpening
angle guide whereby a knife blade may be received with the cutting
edge extending a distance outside the guide for being sharpened at
a proper angle defined by the blade sharpening guide, which is, for
example, disclosed in U.S. Patent 2437495 of Anderson and my
Canadian Patent Application 2133910. In the latter, the blade
sharpening angle guide comprises an elongated block having a planar
top, two side faces inclining one towards another and a bottom,
whereby a truncately triangular cross-section is formed. The block
further comprises a longitllAl n~ 1 slot extending along the whole
length of the bottom and being orthogonal to the planar top,
whereby the knife blade may be received with the cutting edge
extending a distance outside the block for being sharpened at a
proper angle on either side when each of the two side faces serves
alternatively as a sharpening device bearing surface.
When a knife blade and blade sharpening angle guide
combination are drawn across the sharpening steel in a sharpening
operation, not only the blade cutting edge but also the bearing
side faces of the blade sharpening angle guide contact the
sharpening surface of the sharpening steel so that the bearing side
faces of the guide is wearing away while the blade cutting edge is
being sharpened. therefore, abrasion-resistant material are usually
expected to be used for the blade sharpening angle guide, which,
however, may cause other difficulty or complexity to the
manufacturing of the blade sharpening angle guide.
In order to solve the problem there is another approach in
which an improved sharpening steel may be used to avoid the guide
wearing away.

213~
Summary of The Invention
An object of the present invention is to provide an improved
sharpening steel adapted for the use of a manual sharpening of the
cutting edge of a knife blade which is held by a blade sharpening
angle guide having two bearing side faces, with the cutting edge
extending a distance outside the guide for being sharpened at a
proper angle.
In accordance with one aspect of the present invention there
is provided a sharpening steel adapted for the purpose set out in
the above object comprises an elongated steel body having two ends
and a handle mounted on one end thereof. the elongated body has a
sharpening portion formed with a sharpening surface and a guiding
portion formed with a smooth guiding surface which has a
longitudinal length not less than a width of the bearing side faces
of the guide. The sharpening surface contacts the blade cutting
edge while the smooth guiding surface contacts the bearing side
faces of the guide when the knife blade and blade sharpening angle
guide combination are drawn across the sharpening steel.
Preferably, the elongated body is a steel rod.
In an embodiment of the present invention the steel rod is
substantially equally divided by the sharpening portion and guiding
portion.
Conveniently, the guiding portion is between the sharpening
portion and the end on which the handle is mounted.
Advantages of the present invention are that instead of the
sharpening surface, an additional smooth guiding surface of the
sharpening steel is provided for contacting the bearing side faces
of the blade sharpening angle guide so that the wearing away of the
guide is avoided.
Further features of the present invention will be apparent
from the following description and appended claims.
Brief Description of The Drawings
The present invention will be further understood from the
following description with reference to the drawings in which
Figure 1, in a side view, illustrates, in accordance with a
preferred embodiment of the present invention, a sharpening steel
having a sharpening portion and guiding portion, co-operating with
a knife blade and blade sharpening angle guide combination which
are shown in the cross-section in a phantom outline.
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2134~11
Detailed Description of The Preferred Embodiment
Referring to Figure 1, there is provided a sharpening steel 10
comprising a steel rod 12 and a handle 14 mounted on one end 15
thereof in a conventional manner. The steel rod 12 has a sharpening
portion 16 formed with a rough sharpening surface 18, a guiding
portion 20 formed with a smooth guiding surface 22 and an interface
line 24 which locates about in the mid of the steel rod 12. The
rough sharpening surface 18 extends from the interface line 24 to
the other end 26 while the smooth guiding surface 22 extends
between the interface line 24 and one end 15 on which the handle 14
is mounted. The sharpening portion and guiding portion have an
identical diameter. The steel rod 12 is about 10 to 12 inches in
its length.
This sharpening steel would be held in a up right position
when using perhaps on a table or cutting board. In a sharpening
operation the smooth guiding surface 22 contacts the bearing side
faces while the cutting edge of the knife blade is sharpened by the
rough sharpening surface 18 when the knife blade and blade
sharpening angle guide combination are drawn across the sharpening
steel.
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Representative Drawing