Knife and blade sharpener

Information

  • Patent Grant
  • 6769327
  • Patent Number
    6,769,327
  • Date Filed
    Thursday, October 17, 2002
    23 years ago
  • Date Issued
    Tuesday, August 3, 2004
    21 years ago
Abstract
A knife sharpener (10) has pairs of overlapping, resiliently flexible fingers or strips (21-23, 31-33) to form opposed sharpening faces (27-29, 37-39) operable to engage at least one cutting edge (101) on a knife blade (102). The sharpening faces (27-29, 37-39) can have abrasive materials and/or surfaces (40-43) to generate the desired finish on the cutting edge(s) (101).
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




THIS INVENTION relates to a knife sharpener.




Throughout the specification, the term “knife” shall include cutting devices and utensils of the type having a handle or grip; at least one cutting blade, which may be fixed, foldable or partially or wholly retractable relative to the handle or grip; the or each cutting blade having at least one cutting edge.




Examples of the cutting devices and utensils included within the term “knife” shall include kitchen knives, butcher's knives, chef's knives, sporting knives, box cutters or so-called “Stanley” (Trade Mark) knives, pocket knives, letter openers or bodkins, and the like.




2. Prior Art




Traditionally, knives such as butcher's knives and chef's knives were sharpened or honed using a honing steel and/or whetstone. However, as many people did not have the necessary skill to use such steels to produce good cutting edges on their knives, many different types of knife sharpeners have been developed over the years. While these knife sharpeners are easier to use for the average person, they generally have one or more practical limitations and so there is still a quest to develop an improved knife sharpener.




SUMMARY OF THE PRESENT INVENTION




It is an object of the present invention to provide a knife sharpener, which is easy to use without the necessity for special skills and which preferably provides a cutting edge which is similar to that produced by a honing steel.




It is a preferred object of the present invention to provide such a knife sharpener, which is relatively simple to manufacture and which may be relatively inexpensive to manufacture.




It is a further preferred object of the present invention to provide a knife sharpener, which can easily be varied in specification to suit the particular knives, which it is intended to sharpen.




It is a still further preferred object to provide such a knife sharpener, which may be freestanding; or which may be incorporated into a knife scabbard or knife block, or affixed to any solid or support surface.




Other preferred objects of the present invention will become apparent from the following description.




In one aspect the present invention resides in a knife sharpener including:




at least one pair of overlapping, resiliently flexible, fingers or strips mountable in and/or on a base; and




abrasive means on at least one portion of Inwardly directed, opposed, sharpening faces on the fingers or strips, operable to engage at least one cutting edge on a blade of a knife (as hereinbefore defined).




The base may be freestanding eg., to rest on a bench, or be mounted on a wall, and may be provided with a handle which preferably extends laterally to a sharpening axis of the sharpener. Alternatively, the base may include, or be incorporated in, a knife scabbard or knife block. Where the base is a knife scabbard or knife block, preferably the fingers or strips extend Into a hole, aperture, slot, or groove in the scabbard or block, or are mounted on a side of the scabbard or block.




Preferably there are two or more pairs of the resiliently flexible fingers or strips provided in the overlapping arrangement.




Preferably one of the, or each pair of fingers is formed integrally with a mounting plate or bracket mountable in or on the base; and the other of the, or each pair of fingers is formed integrally with a second plate or bracket.




Preferably the fingers or strips are offset relative to the plane of the mounting brackets or plates and are curved or angled relative thereto in side view.




The fingers or strips may be formed from resilient material including metals and their alloys; polymeric materials; composite materials; elastomeric materials and/or a combination of two or more of these and the materials may be reinforced eg., with metal fibres, plastic fibres, carbon fibres, or other suitable materials.




The abrasive means may include abrasive material and/or abrasive surfaces.




The abrasive materials may include sapphires and other hard gems, diamond dust or crushings; manufactured abrasives, including diamond-like carbon and carborundum; natural abrasives eg., stone; hard metal alloys, such as WC, CrC, VC; hard ceramics and their composites; and/or a combination of two or more of these. The selection of the particular abrasive material(s) and the grit sizes may be varied to suit the particular composition of the steels/alloys of the blades and the desired finish of the cutting edges.




The abrasive surfaces may be mechanically treated surfaces, such as grooves, knurling, random pitting or shot-blasting, or may be smooth, unmolested surfaces. The mechanically-treated surfaces may be similar to hard-chrome or hardened carbon steels, which may be coated with a hard surface (eg., hard chromed), hard or soft platings, or uncoated. Smooth surfaces are particularly suitable for fine honing of the cutting edges.











BRIEF DFSCRIPTION OF THE DRAWINGS




To enable the invention to be fully understood, preferred embodiments will now be described with reference to the accompanying drawings in which:





FIG. 1

is a schematic, perspective view of a first embodiment of a knife sharpener in accordance with the present invention;





FIGS. 2 and 3

are perspective views of the fingers and associated mounting plates suitable for the embodiment of

FIG. 1

;





FIG. 4

is an end elevational view of a second embodiment;





FIG. 5

is a perspective view of a third embodiment; and





FIGS. 6

to


9


are perspective views of alternative abrasive surfaces on the fingers or strips.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




Referring to

FIG. 1

, the knife sharpener


10


of a first preferred embodiment of the present invention, to be hereinafter described, is designed to provide a sharp cutting edge


101


to the blade


102


of a knife


100


having a handle


103


.




The sharpener


10


has a body


11


with a body flange


12


and optional backing plate


13


which may be bolted or fastened together by suitable bolts or fasteners


16


.




A handle


14


is attached to, or formed integrally with, the body so flange


12


, and extends substantially at right angles to the sharpening axis of the knife sharpener


10


(along which knife


100


is shown to extend). A finger guard


15


, of any suitable shape, overlies the handle


14


so that the handle


14


is squeezed by the user's hand/fingers and the guard


15


protects the hand/fingers against downward, accidental movement, of the knife blade


102


.




As shown more clearly in

FIGS. 2 and 3

, a pair of sharpening members


20


,


30


are clamped to the body flange


12


so that the respective fingers


21


-


23


and


31


-


33


are arranged in an overlapping relationship shown in

FIGS. 1 and 3

.




In the specific embodiment illustrated, the sharpening members


20


,


30


are formed eg., by cutting and pressing from sheet metal. Each sharpening member


20


,


30


has a mounting plate


24


,


34


with holes


25


,


35


to allow the fasteners


16


to pass therethrough. The fingers


21


-


23


and


31


-


33


are curved and are outwardly offset relative to the mounting plates


24


,


34


and are connected thereto by substantially S-shaped intermediate sections


26


,


36


, so that the lower portions of the fingers


21


-


3


,


31


-


33


are spaced, and the fingers then overlap to form opposed sharpening faces


27


-


29


and


37


-


39


respectively.




Abrasive material


40


eg., fine diamond dust (see

FIG. 6

) is applied to the sharpening faces


27


-


29


,


37


-


39


, eg., by suitable adhesive or coating or plating means.




The operation of the sharpener will now be described with reference to FIG.


1


.




The knife blade


101


is placed in the “valley” formed by the overlapping fingers


21


-


23


,


31


-


33


so that the cutting edge


101


engages the sharpening faces


27


-


29


,


37


-


39


. As the knife


100


is pulled away from the sharpener


10


, or pushed towards it, preferably with at least some downward pressure, the abrasive material on the sharpening faces


27


-


29


,


37


-


39


grinds, or abrades, the cutting edge


101


to improve the quality of the cutting edge


101


.




The blade


102


may be passed between the opposed fingers


21


-


23


,


31


-


33


one or more times until the desired quality of cutting edge


101


is achieved.




In alternative embodiments, the sharpening faces


27


-


29


,


37


-


39


can be mechanically treated to provide an abrasive surface that is non-abrasive particle based. The mechanically treated surfaces can incorporate grooves or knurling


41


, random-pitting


42


, a shot-blasted, eg., in the nature of standard hard-chromed or hardened carbon steels—see

FIGS. 7 and 8

.




In a further alternative embodiment, the sharpening faces


27


-


29


,


37


-


39


can have smooth, unmolested surfaces, eg., for fine honing of the cutting edges.




The abrasive surfaces may be coated


43


, eg,. with hard-chrome, hard or soft plating materials (see FIG.


9


); or may be left unplated (eg., bare metal).




In a still further alternative embodiment, aftemative sharpening faces


27


-


29


,


37


-


39


may have abrasive materials and abrasive surfaces respectively; or the sharpening faces


27


-


29


,


37


-


39


may have both abrasive materials and abrasive surfaces.




As the fingers


21


-


23


,


31


-


33


are resiliently flexible, they can accommodate different blade thicknesses, cutting edge profiles and/or degree of downward pressure applied to the knife blade


102


.




It will be readily apparent to the skilled addressee that the number of pairs of fingers; the curvature and angle and offset of the fingers; the construction of the fingers (eg., metal/metal alloys/fibre reinforced plastics); grit of the sharpening faces; type of abrasive material(s)/surface(s); width size of the abrasive material(s)/surface(s); and other desired details may be varied to suit the particular intended application, or manufacturing expediency.




Where the fingers are formed from plastics, composites and/or elastomeric materials, they may be moulded to shape and may incorporate fibre reinforcing materials (eg., metal fibres, glass fibres, carbon fibres).




It will be readily apparent to the skilled addressee that the knife sharpener


10


may be free standing, eg., to be used on a bench; or may be mounted eg., on a suitable support or bracket


50


on a wall or workbench


60


, as shown in FIG.


4


.




The knife sharpener


10


may also be provided in a knife scabbard or knife block


70


, where the sharpening members


20


,


30


are mounted within the body


71


of the scabbard or block; and the fingers


21


-


23


,


31


-


33


extend Into a hole, aperture, groove or slot


72


within, or on, the body


71


of the scabbard or block


70


.




It will be readily apparent to the skilled addressee that various other changes and modifications may be made to the embodiments described and illustrated without departing from the present invention.



Claims
  • 1. A knife sharpener including:at least one pair of overlapping, resiliently flexible, fingers or strips mountable in and/or on a base; abrasive means on at least one portion of inwardly directed, opposed, sharpening faces on the fingers or strips, operable to engage at least one cutting edge on a blade of a knife; and a handle attached to the base and at a right angle to a blade of a knife being sharpened.
  • 2. A knife sharpener including:at least one pair of overlapping, resiliently flexible, fingers or strips mountable in and/or on a base; and abrasive means on at least one portion of inwardly directed, opposed, sharpening faces on the fingers or strips, operable to engage at least one cutting edge on a blade of a knife the base is a knife scabbard or knife block, and the fingers or strips extend into a hole, aperture, slot, or groove in the scabbard or block, or are mounted on a side of the scabbard or block.
  • 3. A sharpener as claimed in any one of claims 1 or 2, wherein:there are two or more pairs of the resilient flexible fingers or strips provided in the overlapping arrangement.
  • 4. A sharpener as claimed in claim 3, wherein:one of the or each pair of fingers is formed integrally with a mounting plate or bracket mountable in or on the base; and the other of the or each pair of fingers is formed integrally with a second plate or bracket.
  • 5. A sharpener as claimed in claim 4, wherein:the fingers or strips are offset relative to the plane of the mounting brackets or plates and are curved or angled relative thereto in side view.
  • 6. A sharpener as claimed in any one of claims 1 or 2, wherein:the fingers or strips may be formed from resilient material including metals and their alloys; polymeric materials; composite materials; elastomeric materials and/or a combination or two or more of these, and the materials are optionally reinforced with metal fibers, plastic fibers, carbon fibers, or other suitable materials.
  • 7. A sharpener as claimed in any one of claims 1 or 2, wherein:the abrasive means includes abrasive material and/or abrasive surfaces.
  • 8. A sharpener as claimed in claim 7, wherein:the abrasive materials include sapphires and other hand gems; diamond dust or crushings; manufactured abrasives, including diamond-like carbon and Carborundum; natural abrasives, including stone; hard metal alloys, including WC, CrC, VC; hard ceramics and their composites; and/or a combination of two or more of these, the selection of the particular abrasive material(s) and the grit sizes being varied to suit the particular composition of the steels/alloys of the blades and the desire finish of the cutting edges.
  • 9. A sharpener as claimed in claim 7, wherein:the abrasive surfaces are mechanically treated surfaces, including grooves, knurling, random pitting or shot-blasting, or are smooth, unmolested surfaces.
  • 10. A sharpener as claimed in claim 9, wherein:the mechanically-treated surfaces are similar to hard-chromed or hardened carbon steels; optionally coated with a hard surface including hard chrome, hard or soft platings; or uncoated.
  • 11. A sharpener as claimed in claim 1 having a guard located above the handle and below the resilient fingers.
  • 12. A knife sharpener including:two or more of overlapping, resilient flexible, fingers or strips; each strip having a sharpening face which is flat across the width of the finger; abrasive means on at least one portion of inwardly directed, opposed, sharpening faces on the fingers or strips, operable to engage at least one cutting edge on a blade of a knife; each pair of fingers being formed integrally with a mounting plate or bracket; the other of each pair of fingers is formed integrally with a second plate or bracket; and the fingers or strips being offset relative to the plane of the mounting brackets or plates and curved relative thereto in side view.
  • 13. A sharpener as claimed in claim 12, wherein:the fingers or strips may be formed from resilient material including metals and their alloys; polymeric materials; composite materials; elastomeric materials and/or a combination or two or more of these, and the materials are optionally reinforced with metal fibers, plastic fibers, carbon fibers, or other suitable materials.
  • 14. A sharpener as claimed in the claim 12, wherein:the abrasive means includes abrasive material and/or abrasive surfaces.
  • 15. A sharpener as claimed in claim 13, wherein:the abrasive materials include sapphires and other hand gems; diamond dust or crushing; manufactured abrasives, including diamond-like carbon and carborundum; natural abrasives, including stone; hard metal alloys, including WC, CrC, VC; hard ceramics and their composites; and/or a combination of two or more of these, the selection of the particular abrasive material(s) and the grit sizes being varied to suit the particular composition of the steels/alloys of the blades and the desire finish of the cutting edges.
  • 16. A sharpener as claimed in claim 13, wherein:The abrasive surfaces are mechanically treated surfaces, including grooves, knurling, random pitting or shot-blasting, or are smooth, unmolested surfaces.
  • 17. A sharpener as claimed in claim 15, wherein:the mechanically-treated surfaces are similar to hard-chromed or hardened carbon steels; optionally coated with a hard surface including hard chrome, hard or soft platings; or uncoated.
Priority Claims (2)
Number Date Country Kind
PR8346 Oct 2001 AU
PS0456 Feb 2002 AU
US Referenced Citations (4)
Number Name Date Kind
2413156 Tarapczynski Dec 1946 A
2509636 Goldstein May 1950 A
4751795 Jeanne Jun 1988 A
5440953 Gangelhoff et al. Aug 1995 A
Foreign Referenced Citations (3)
Number Date Country
02445135 Aug 2003 EP
2556638 Jun 1985 FR
517242 Jan 1940 GB