US2475110A - Knife sharpener - Google Patents

Description

Patented July 5, 1949 UNITED STATES PATENT OFFICE 3 Claims.

This invention relates to, and it is an object to provide, a knife sharpener of novel construction and function; the device being adapted for household as well as commercial use to readily and quickly sharpen kitchen and utility knives, butcher knives, etc.

Another object of the invention is to provide a knife sharpener which is every-ready and easy to use; the device being small, compact, and arranged for fixed attachment to a supporting surface, such as a table top, counter, or the like.

A further object of this invention is to provide a knife sharpener which includes a pair of circular grinding stones or wheels disposed in upwardly diverging relation to form a knife receiving slot therebetween; the grinding wheels interengaging at the bottom portion whereby to positively work in contact with both sides of the V- edge of a knife drawn between such wheels.

An additional object of the invention is to provide a novel supporting body or carrier for the grinding wheels; the latter being r-otatably disposed in said carrier, and means being included to manually accomplish rotation of the grounding wheels to such extent as necessary to distribute the wear thereon.

A further object of the invention is to provide a simple, practical, convenient, and durable knife sharpener which will be extremely effective for the purpose for which it is designed.

These objects are accomplished by means of such structure and relative arrangement of parts as will fully appear by a perusal of the following specification and claims.

In the drawings:

Fig. 1 is a face elevation of one of the grinding wheels, detached.

Fig. 2 is a face elevation of the cooperating grinding wheel, detached.

Fig. 3 is a transverse sectional elevation of the device.

Fig. 4 is an elevation of one of the grinding wheel holders looking toward the circular seat therein.

Fig. 5 is a face elevation of a modified form of grinding wheel, detached.

Fig. 6 is a cross sectional elevation of the same.

Fig. 7 is a face elevation of the modified form of grinding wheel which cooperates with the wheel as shown in Fig. 5, detached.

Fig. 3 is a cross sectional elevation of the grind- Above the base 2 the carrier l includes a pair of generally circular upstanding holders 4 disposed in facing relation and diverging in an upward direction.

The holders 4, on adjacent faces, are formed with annular seats 5 adapted to receive the grinding stones or wheels.

The circular grinding stones or wheels are indicated generally at 6, and a pair thereof is included in the device; one grinding wheel enga ing in the seat 5 of one holder 4, while the other grinding wheel is disposed in the seat of the other holder; the grinding wheels thus being disposed in upwardly diverging relation to each other whereby to form a V-slot S therebetween, as shown. Opposite ends of the carrier are closed except for vertical, knife guide slots 1, straight and only knife width, alined with each other and disposed in a plane centrally between the grinding wheels.

The lower portion of the grinding wheels 6 interengage in the following manner, so that such V-slot S feathers out short of the bottom of said Wheels:

The adjacent faces of the grinding wheels 6 are formed with a plurality of alternate, segmental recesses 8 and grinding segments 9; the grinding segments 9 meshing at the bottom portion of said wheels, in the recesses 8; the latter being oversize to an extent to permit engaging of the segments on the downward course of the grinding wheels and free disengagement thereof on the upward course of the same.

One of the grinding wheels *6 has a non-circular nut Ill embedded centrally therein, and a spindle H is threaded into said nut and projects axially outwardly through an opening [2 on the corresponding holder 4. outwardly of u h opening the spindle II is formed with a hand nub, or the like, I3. When the above described device is in use, a knife is placed in the guide slots 1 of the carrier l and extends through the V-slot S between the grinding wheels, then engaging evenly on both sides of the cutting edge with the corresponding working faces of said grinding wheels 6 at the bottom of the V-slot S. By drawing the knife lengthwise between such grinding wheels 6, the knife edge is effectively sharpened for its full length; the hand knob [3 then being held to prevent turning or creeping of the grinding wheels during the sharpening operation.

The wheels 6 may be rotated, by the hand knob [3, between sharpening operations, as is desirable to distribute the wear on the grinding wheels so that the same will be evenly worn by use.

The described knife sharpener provides a device which is ever-ready and convenient to use; the sharpening of a knife being a simple manual operation, requiring little time or dexterity.

In Figs. 5-8, inclusive, there is illustrated a. modified form of the grinding stones or wheels.

Here the. circular grindings whfifils lndicated generally at M; include radially spaced annulargrinding surfaces or rings l5 having annular 5 recesses l6 therebetween.

When the grinding wheels 14 are mounted in the supporting body or carrier I, the annulargrinding surfaces I5 and the annular,,.1.recessest l6, which are alternately arranged on the respec-' tive Working faces of the wheels runl-imimter-= engagement at the bottom portions of said. w,heels; i. e. the annular grindingsurfaces iii of one wheel run in the annular recesses l6 of the other wheel. There is thus accomplished-a bettorn-lapping 'of the Wheels so as to feather;out the wslot*S forknife sharpening engagement. Also,- the-interengagement of the grinding wheels l4 permits oneto turn the other,- and nnle' of said' wheelsl4 includes a center nut i'l forthe-samepurpose as th nut 10. The grinding wheelsll may thus be revolved to different positions in order to distribute the wear thereon;

This typ of grinding Wheels is--used when-the knife to be sharpened is hollow grouncl ova-relatively thin blade.

In both forms of-constructionas above described it will be appreciatedthat the backs of the grinding wheels present relatively-broad flat surfaces which frictionally engage the seats in the holders 4.- As these surfaces are-so much greater in area than: those portions of the op posed faces of the grinding wheels engaged by the knife edge, the grinding wheels willnot rotate within the holders 4 duringsharpenin'g although they may otherwise -befree to do so. When the knife to be sharpened is placed in the V-slot'l and pressed downwardly betwen -th'e grinding wheels, the grinding wheels are spread or pressed outwardly against the seats 0f--the holders 4.- They will consequentlybe frictionally held rigid and immobilewhlle the-knife-is being drawn therebetween.

It will also be observed that the ends of the carrier 1 are open so that 'when the knife to be sharpened is positioned 'in the slot 1 for receptiontherein or to be drawntherethroughg the knife will;engage each grinding wheel; on itsflat inner face on opposite sides of its-centerpr in other words, on opposite sides of its vertical 50 diameter. This engagement between -the- -knife and each-grinding wheel on opposite -sid'es thereof avoids any tendency of the grinding; wheels to rotate in their holders under the in'fliiemi of the knife drawn therebetween. This 'allow's'kthe 55 frictional engagement between the backs of the grinding wheels and the holders to be full'y effective to resistrotation and remainrigld'and immobile. Whenever the knife is, withdrawnfrom the sharpener so thatno outward pressure isap plied o the i d nsowheels. t n a j ma n ally rotated to present newpr fresh surfacesgfor engagement by the knife edge sq that wear oil e, inding whee s ay. be. n stribute om t e ore o n giescri tion i w lgbe read l en-that th as e n rn lu e su hia devi as s s n ly ill he p iect ...of.; a mzen: on set forth vl ere i...

h l this p tific ti nsetsiforth.in d ailthe present and preferred construction of the device, still in r ct asuch. devlationsfmm. suc et l. be r ert d t .a wdenqtvf rm a 1 r- Pat frvmihe ir'it ithe i re tionrassi d byt ap endedic ei i a. I

Having thus described theinvention, the fol- 4. lowing is claimed as new and useful and upon which Letters Patent is desired:

1. A. knifea sharpener. comprising a. carrier presenting two opposed;seats;; grinding wheels positioned on said seats presenting opposed faces that converge towards interengaging portions of the grinding wheels enabling a knife edge to be dr 'awn therebetween to effect sharpening, said seatspresenting surfaces adapted to be frictionally engaged by the backs of the grinding wheels whennthevkrnfeiiedge placed therebetween urges the grinding wheels outwardly so that the grinding wheels will be frictionally held rigid and immobile on the seats by the knife but enable the grinding--wheels' -tobe rotatablyadjusted relativelyto the seats to: presentrdifferent= surfaces for engagementby thesides of the. knife edgea 23A knife sharpener comprising a carrier presenting-- two opposed seats,-. grinding wheels positioned on said seats presenting' opposed faces that converge towards :interengaging-portions: of the grinding-wheelsenablinga knife edge tosbe drawntherebetween-to effect sharpening-,- said seatspresenting surfaces" adapted to be: frice tionall'y' engaged by the backs of'the grinding Wheels when the knife =edge placed therebetween urgesthe grinding wheels outwardly so that the grinding; wheels will be frictionally: held-rigid and immobile -on the seats by the knife *but -enablethe grinding wheels to: be rotatably adjusted relatively to the seats-to present" different :sur-. faces-for'engagement-by the-sides-ofthe knife edge, the carrier'b'eingmpen at'opposite' ends of the slot formed between the-converging faces of the grinding-wheels enabling theknife edge to be I positioned =therebetween= and engage --eaoh grinding wh'eelon opposite sidesof'the' center thereof.-

3; A knife sharpener comprising a carrier -havinga base and upwardly divergent holders there-' on, the holders'presenting upwardly divergent seats grinding wheels, positioned on saidseats presentingopposed faces that converge down= walldly towards; inte neae ng portions 0.111 the grinding-Wheels enabling a knife edge to be drawn thereb'etween to effect, sharpening, the seats, on the holders presenting surfaces adapted to be frictionally engaged by the backs. of the grinding wheelssothattheir rotation .Willbe resisted when a knife edge is pressed between the. grinding wheels ,to urge; them outwardly but enabling .the grinding wheels to be rotatably. adjusted; rela= tivel-y to-thgparrieh the ends. of the carrier being open to permit the knife to be inserted in sucha manner as .-;to,-, engage. each grinding 3 wheel: i on oppositeisides of the [center: thereof LEO E. PRYOR;v

REFERENCES eCITEDn The, following references'are of record in the file ofnthis patent:-

UNITED; STATES. PATENTS Number Name Date 726,974 McLeran May-5,1903 1,606,813 Schultz Nov .-16,='1926 134:6;3115 Gomeau Feb. 2, 1934 2,264,065 Broberg Nov.-25',--'194{1 2,378,754 DeMi1lar-- June 19,4945 2,420,814 Clarkfi. Maw-20.1947

EOBEI N PAT YENTS Number Country Date 539,378 Germany Nov=. 2'l ,11931

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