U.S. patent application number 12/647435 was filed with the patent office on 2010-04-22 for knife sharpener.
Invention is credited to Hung-Nung Tsai.
Application Number | 20100099338 12/647435 |
Document ID | / |
Family ID | 42109054 |
Filed Date | 2010-04-22 |
United States Patent
Application |
20100099338 |
Kind Code |
A1 |
Tsai; Hung-Nung |
April 22, 2010 |
Knife Sharpener
Abstract
A knife sharpener comprises a base, a motor, a grinding wheel
assembly, a rotary shaft and two springs. The working channel
between the edge of the grinding disc and the grinding awl is
automatically adjustable to accommodate different blade of
different thickness. When the knife sharpener performs grinding
operation, the grinding wheel assembly can simultaneously grind
both cutting sides of the knife. In addition, the knife can be
clamped firmly through the three contacting areas of the grinding
disc, the grinding awl, and the cutting edge, so that the operation
of knife grinding can be successfully performed.
Inventors: |
Tsai; Hung-Nung; (Taichung
County, TW) |
Correspondence
Address: |
Dr. BANGER SHIA;Patent Office of Bang Shia
102 Lindencrest Ct.
Sugar Land
TX
77479-5201
US
|
Family ID: |
42109054 |
Appl. No.: |
12/647435 |
Filed: |
December 25, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11626844 |
Jan 24, 2007 |
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12647435 |
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Current U.S.
Class: |
451/192 ;
451/224 |
Current CPC
Class: |
B24B 3/54 20130101 |
Class at
Publication: |
451/192 ;
451/224 |
International
Class: |
B24B 3/54 20060101
B24B003/54 |
Claims
1. A knife sharpener capable of sharpening a cutting edge of a
knife, the cutting edge of the knife including a first side and a
second side, the knife sharpener comprising: a base defined with a
receiving space for installation of grinding assemblies, a
plurality of slots connecting with the receiving space being
defined in a top surface of the base; a motor serving as a power
source of the knife sharpener being assembled at one side of the
receiving space; at least one grinding wheel assembly including two
assembling members, a grinding disc and a grinding awl, each
assembling member being provided with a bearing, the two assembling
members being distantly disposed in the receiving space, so that
the grinding disc is located between the two assembling members,
the grinding disc has two surfaces, one of which is an
annular-shaped grinding surface for grinding the cutting edge, and
a through hole formed in the middle of the grinding disc, the
grinding awl being located between the two assembling members in
such a manner that one surface of the grinding awl abuts against
the grinding surface of the grinding disc, another surface of the
grinding awl is rested against a fixing member, a surface of the
grinding awl facing the grinding surface is a tapered grinding
surface with a taper angle of 9-45 degrees, which serves as another
grinding surface of the knife sharper, a through hole formed in the
middle of the grinding awl, the grinding disc and the edge of the
grinding awl being located in a certain distance away from each
other to form a working channel to be aligned with one of the
slots; a rotary shaft having one end fixed to a rotor of the motor,
so that it is rotated by the motor, another end of the rotary shaft
in turn passing through the bearing of the assembling member, the
through hole of the grinding awl, the through hole of the grinding
disc and the bearing of another assembling member, so that the two
bearings and the grinding awl are fixed on the rotary shaft, that
the grinding disc is moveable along the rotary shaft, and the
rotary shaft is able to rotate the grinding disc and the grinding
awl to grind the knife; two springs, one spring having one end
biased against the grinding disc, another spring having one end
biased against the grinding awl, so as to keep the grinding surface
of the grinding disc and the tapered grinding surface of the
grinding awl close to each other under normal conditions, when the
cutting edge of a knife is being ground in the working channel, the
first side of the cutting edge being in contact with the
annular-shaped grinding surface at two contacting areas, while the
second side of the cutting edge being in contact with the tapered
grind surface at one contacting area, the cutting edge can move the
grinding disc to make the grinding surface and the tapered grinding
surface move slightly in horizontal direction, while the tapered
grinding surface can keep the cutting edge from overly moving
downwards, so that the annular-shaped grinding surface and the
tapered grinding surface can properly contact the cutting edge.
2. The knife sharpener as claimed in claim 1, wherein three
restricting ribs are distantly mounted in an inner surface of the
receiving space, while three engaging grooves are formed in an edge
of the assembling members and three engaging grooves are formed on
an outer surface of a housing of the motor to mate with the
restricting ribs, so that the assembling members and the motor are
stably assembled in the receiving space.
3. The knife sharpener as claimed in claim 1, wherein a receiving
concave is defined in the annular-shaped grinding surface of the
grinding disc, and iron chips produced during the course of
grinding will fall into the receiving concave.
4. The knife sharpener as claimed in claim 1, wherein the rotary
shaft is hexagonal-shaped, and the through hole of the grinding
disc is a hexagonal hole accordingly, so that the rotary shaft is
able to rotate the grinding disc and the grinding awl to grind the
knife.
5. The knife sharpener as claimed in claim 1, wherein a magnet is
defined in the base for attracting iron chips and preventing the
iron chips from flying in all directions, and a user can easily
take out the magnet to clean out the iron chips.
Description
[0001] This application is a continuation of part of U.S. patent
application Ser. No. 11/626,844, which claims the benefit of the
earlier filing date of Jan. 24, 2007. Claim 1 of this application
is revised from the claim 1 of the U.S. patent application Ser. No.
11/626,844, claims 2, 3, 4 and 5 of this application correspond to
claims 2, 3, 4 and 5, of the U.S. patent application Ser. No.
11/626,844, respectively.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a knife sharpener, and more
particularly to a knife sharpener, wherein a high-speed running
grinding wheel assembly is driven by motor power to perform
grinding operation.
[0004] 2. Description of the Prior Art
[0005] There are various types of knife sharpeners, which mainly
include manual knife sharpener and power driven knife sharpener.
What is to be discussed in the present invention is a power driven
grinding wheel assembly for grinding knife. Referring to FIG. 1, a
conventional electric knife sharpener with a single grinding wheel
is shown and comprises a disc-shaped grinding wheel 11 disposed in
a body 10, and on each side of the grinding wheel 11 is formed a
slantwise opening 12 for receiving a knife 13. A user can hold the
knife 13 and move it to and fro in a longitudinal direction to
grind the both sides of cutting edge by the both sides of the
grinding wheel 11.
[0006] When using the conventional knife sharpener to perform
grinding operation, the grinding wheel cannot simultaneously grind
the both sides of a knife. It can only grind one side at a time.
This grinding manner would render the end of cutting edge to curve
toward another end for the cutting edge is pushed by the power of
the grinding wheel, so that the after-grinding knife is not likely
to be sharp. Therefore, when performing grinding, the user has to
alternately grind each side of the cutting edge, so as to avoid one
side of the cutting edge from being overly grinding.
[0007] Therefore, when performing grinding, if the two sides of the
cutting edge can be ground at the same time, it not only can solve
the deformation of one side of the cutting edge caused by
conventional grinding manner, but also can improve the efficiency
of grinding and relieve from the fussy operation.
[0008] The present invention has arisen to mitigate and/or obviate
the afore-described disadvantages.
SUMMARY OF THE INVENTION
[0009] The primary objective of the present invention is to provide
a knife sharpener, particularly to a knife sharpener, wherein a
high-speed running grinding wheel assembly is driven by motor power
to perform grinding operation. The grinding surface of an
annular-shaped grinding disc contacts one side of the cutting edge
of a knife at two contacting areas to perform grinding operation,
meanwhile, the tapered grinding surface of a grinding awl contacts
the other side of the cutting edge of the knife at one contacting
area to perform grinding operation. By such a manner, the grinding
disc and the grinding awl can prevent the knife from excessively
shaking and improve the stability of the operation.
[0010] The secondary objective is to provide a knife sharpener,
when the knife is placed in the working channel between the edge of
the grinding disc and the grinding awl, the cutting edge can push
the grinding disc slightly outward to enlarge the space between the
grinding disc and the grinding awl, a thin cutting edge makes a
narrow space, and a thick cutting edge makes a wide space. In
addition, the awl of the tapered grinding surface of the grinding
awl can keep the cutting edge from overly moving downwards. In
other words, the space of the working channel can cooperate with
the awl of the tapered grinding surface to deal with cutting edge
with different thickness, so that when cutting edge of knives with
different thickness is to be ground, it can properly contact the
grinding disc and the grinding awl.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a perspective view of a conventional electric
knife sharpener with a single grinding wheel;
[0012] FIG. 2 is an exploded view of a knife sharpener in
accordance with the present invention;
[0013] FIG. 3 is an amplified view of the grinding wheel in
accordance with the present invention;
[0014] FIG. 4 is an amplified view of the grinding awl in
accordance with the present invention;
[0015] FIG. 5 is an assembly view of the knife sharpener in
accordance with the present invention;
[0016] FIG. 6 is a longitudinal section view of the knife sharpener
in accordance with the present invention;
[0017] FIG. 7 is a transverse section view of the knife sharpener
in accordance with the present invention;
[0018] FIG. 8 is a transverse section view of showing that the
knife sharpener in accordance with the present invention is
grinding the cutting edge of a knife;
[0019] FIG. 9 is an amplified view of FIG. 8;
[0020] FIG. 10 is a longitudinal section view of showing that the
knife sharpener in accordance with the present invention is
grinding a knife with thin cutting edge;
[0021] FIG. 11 is a longitudinal section view of showing that the
knife sharpener in accordance with the present invention is
grinding a knife with a thick cutting edge; and
[0022] FIG. 12 is a perspective view in accordance with the present
invention of showing that iron chips are produced during the course
of knife sharpening.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0023] The present invention will be clearer from the following
description when viewed together with the accompanying drawings,
which show, for purpose of illustrations only, the preferred
embodiment in accordance with the present invention.
[0024] Referring to FIGS. 2-10, a knife sharpener in accordance
with a preferred embodiment of the present invention is capable of
sharpening the cutting edge 71 of a knife 70, and the cutting edge
71 includes a first side 711 and a second side 712. The knife
sharpener comprises a base 20, a motor 30, a grinding wheel
assembly 40, a rotary shaft 50 and two springs 60, 62.
[0025] The base 20 is defined with a receiving space 21 for
installation of the grinding assembly. Three restricting ribs 22
for fixing the grinding assembly are distantly formed in the inner
surface of the receiving space 21. A plurality of slots 23
connecting with the receiving space 21 is defined in the top of the
base 20, and each slot 23 is wide in the middle section and narrows
toward both ends thereof.
[0026] The motor 30 is a power source of the knife sharpener. In
the outer surface of the housing of the motor 30 are defined three
engaging grooves 31 to mate with the restricting ribs 22 in the
inner surface of the base 20, so that the motor 30 can be stably
fixed at one side of the receiving space 21.
[0027] The grinding wheel assembly 40 includes two assembling
members 41a, 41b, a grinding disc 42 and a grinding awl 43. Each
assembling member 41a, 41b, is mounted a bearing 411a, 411b, and
three engaging grooves 412 are formed in the fringe of each
assembling member 41a, 41b, to mate with the restricting ribs 22 in
the receiving space 21. The two assembling members 41a, 41b, are
distantly assembled to render the grinding disc 42 assembled
between them. The grinding disc has two surfaces, one of which is
an annular-shaped grinding surface 421 for grinding cutting edge.
In the inner side of the annular-shaped grinding surface 421 is
defined a receiving concave 422, and a through hole 423 is formed
in the middle of the grinding disc 42. The grinding awl 43 is
located between the two assembling members 41a, 41b in such a
manner that one surface abuts against the grinding surface 421 of
the grinding disc 42, another surface is rested against a fixing
member 44. The surface of the grinding awl 43 facing the grinding
surface 421 is a tapered grinding surface 431 with a taper angle of
9-45 degrees, and the grinding surface is another grinding surface
of the knife sharpener of the present invention. A through hole 432
is formed in the middle of the grinding awl 43. Under normal
conditions, the awl 433 of the grinding awl 43 rests against the
receiving concave 422 of the grinding disc 42, while the grinding
disc 42 and the edge of the grinding awl 43 are located in a
certain distance away from each other to form a working channel 45,
which is to be aligned with the slot 23 for allowing the knife to
be inserted into the working channel through the slot 23.
[0028] The rotary shaft 50 has one end fixed to a rotor of the
motor 30, so that it can be driven by the motor. Another end of the
rotary shaft 50 in turn passes through the bearing of the
assembling member 41a, the through hole 432 of the grinding awl 43,
the through hole 423 of the grinding disc 42 and the bearing of
another assembling member 41b, so that the two bearings and the
grinding awl 43 are fixed on the rotary shaft 50. The rotary shaft
50 is hexagonal-shaped, and the through hole 423 of the grinding
disc is a hexagonal hole accordingly, so that the rotary shaft is
able to rotate the grinding disc 42 and the grinding awl 43 to
grind the knife.
[0029] The spring 60 is biased between the grinding disc 42 and
another fixing member 61, and the spring 62 is biased between the
grinding awl 43 and the fixing member 44, so as to keep the
annular-shaped grinding surface 421 of the grinding disc 42 and the
tapered grinding surface 431 of the grinding awl 43 close to each
other under normal conditions. When the cutting edge 71 of a knife
70 is being ground in the working channel 45, the first side 711 of
the cutting edge 71 contacts the annular-shaped grinding surface
421 at two contacting areas A and B (as shown in FIGS. 9 and 10),
while the second side 712 of the cutting edge 71 is in contact with
the tapered grind surface 431 at one contacting area C. The cutting
edge 71 can move the grinding disc to make the annular-shaped
grinding surface 421 and the tapered grinding surface 431 move
slightly in horizontal direction, while the awl of the tapered
grinding surface 431 can keep the cutting edge 71 from overly
moving downwards, so that the grinding surface 421 and the tapered
grinding surface 431 can properly contact the cutting edge 71, and
the working channel 45 is accordingly adjusted to the appropriate
width corresponding to the thickness of the cutting edge 71.
[0030] Abovementioned is an illustration of the location and the
structure of the respectively related subassemblies of the present
invention. When the knife sharpener performs grinding operation,
the grinding wheel assembly can simultaneously grind both sides of
the cutting edge of the knife. In addition, the present invention
can clamp the knife firmly through the three contacting areas of
the grinding disc, the grinding awl, and the cutting edge, so that
the operation of knife grinding can be successfully performed. The
following is the description of the operation state of the present
invention:
[0031] Referring to FIGS. 8-10, the grinding wheel assembly 40 of
the present invention performs the grinding operation by contacting
the cutting edge 71 with the grinding disc 42 and the grinding awl
43. During the grinding process, the user can hold the knife 70 and
place the cutting edge downwards into the slot 23 of the base 20,
so that the cutting edge 71 contacts the high-speed running
grinding disc 42 and the grinding awl 43, to perform grinding
operation, as shown in FIG. 7.
[0032] As shown in FIGS. 6-7, it is noted that the springs 60 and
62 are disposed at one side of the grinding disc 42 and the
grinding awl 43 of the grinding wheel assembly 40 to push the
grinding disc 42 and the grinding awl 43 towards each other, so
that under normal conditions, the awl of the grinding awl 43 keeps
contacting the grinding disc 42. When the knife 70 is placed in the
working channel 45 between the edge of the grinding disc 42 and the
grinding awl 43, the cutting edge 71 can push the grinding disc 42
slightly outward to enlarge the space between the grinding disc 42
and the grinding awl 43, so that cutting edges 71 with different
thickness can adjust the space of the working channel 45 between
the grinding disc 42 and the grinding awl 43. Namely, as shown in
FIG. 10, a thin cutting edge 71 makes a narrow space, and as shown
in FIG. 11, a thick cutting edge 71 makes a wide space. In
addition, the awl of the tapered grinding surface 431 of the
grinding awl 43 can keep the cutting edge 71 from overly moving
downwards. In other words, the space of the working channel 45 can
cooperate with the awl of the tapered grinding surface to deal with
cutting edge 71 with different thickness, so that when cutting edge
71 of knives 70 with different thickness is to be ground, it can
properly contact the grinding disc 42 and the grinding awl 43.
[0033] It is also noted that when the user grinds the knife 70, the
first side 711 of the cutting edge 71 contacts the annular-shaped
grinding surface 421 of the grinding disc 42 to perform grinding
operation. In the present invention, the inner side of the grinding
surface 421 is defined the receiving concave 422, as shown in FIGS.
8-9. The grinding surface 421 contacts the first side 711 side of
the cutting edge 71 through two contacting areas A and B to perform
grinding operation, while the tapered grinding surface 431 of the
grinding awl 43 contacts the second side 712 of the cutting edge 71
at the contacting area C to perform grinding operation. In other
words, the grinding surface 421 and the tapered grinding surface
431 have three contacting areas A, B and C to contact and grind two
sides of the cutting edge 71 simultaneously. As compared with
traditional single-contacting point grinding operation, the prevent
invention can improve stability between the knife 70 and the
grinding wheel assembly 40.
[0034] Further, when grinding the knife, the user holds the knife
70 and moves it back and forth in a direction tangent to the
running grinding wheel assembly 40. During the course of the user
moving the knife 70 back and forth, the knife 70 is likely to shake
in a non-linear fashion, but the present invention can prevent the
knife 70 from excessively shaking and improve the stability of the
operation by clamping the knife 70 with the grinding disc 42 and
the grinding awl 43 at three contacting areas.
[0035] In addition, in the inner side of the grinding surface 42 is
defined the receiving concave 422. During the course of grinding,
as shown in FIG. 11, iron chips 80 will be produced between the
annular-shaped grinding surface 421 and the tapered grinding
surface 431, and because of gravity, iron chips 80 will fall into
the receiving concave 422 and will finally be collected on the
bottom of base 20. During this course, the receiving concave 422
provides a space for temporarily receiving iron chips 80, so as to
avoid iron chips 80 from being accumulated on the grinding surface
421 and the tapered grinding surface 431, which will influence the
effect of grinding operation. Furthermore, at the bottom of the
base 20 can be disposed a magnet 90 for attracting iron chips 80
and keeping iron chips 80 from flying in all directions, and the
user can easily take out the magnet 90 to clean out iron chips
80.
[0036] While we have shown and described various embodiments in
accordance with the present invention, it is clear to those skilled
in the art that further embodiments may be made without departing
from the scope of the present invention.
* * * * *