US1417054A

US1417054A - Knife sharpener

Info

Publication number: US1417054A
Application number: US452197A
Authority: US
Inventors: Martin T Graf
Original assignee: FRANK X IRR
Current assignee: FRANK X IRR
Priority date: 1921-03-14
Filing date: 1921-03-14
Publication date: 1922-05-23
Anticipated expiration: 1939-05-23

Description

M. T. .GBAF. KNIFE SHARPENER.

APPLICATION FILED MAR. I4, 192!- Patented May 23, 1922. 7

inanrrn r. sitar, or BUFFALO, new "roan, assrsnon or nun-Hahn 'ro rnanir IRE, OI BUFFALO, NEW YORK.

KNIFE SHARPENER.

Application filed March 14,

To all whom it may concern: 1

Be it known that I, MARTIN T. Gear, a citizen of the United States, residing in Buffalo, in the county of Erie and State of New York, have invented new and useful Improvements in Knife Sharpeners, of which the following is a specification.

This invention relates to a knife sharpener which is more particularly designed for sharpening kitchen knives and the like.

It is the object of this inventionto produce a sharpener for this purpose which i will permitof readily and conveniently putting a keen cutting edge on a knife, either on one or both sides thereof, by drawing the knife one or more times past the sharpening surface of the tool, and so constructing this sharpener that the same can be produced at comparatively low cost, that the same will be safe in use, that the cutting teeth will re @lmain sharp for a comparatively long time and that the cutting teeth of the same will i be cleared. of chips or metallic dust and plan view of the same.

therefore not become clogged so that the cuttin efficiency 1s not impaired.

In t 1e accompanying drawings: Figure 1 is an elevation of the preferred form of my improved knife sharpener. Figure 2 is a top Figure 3 is a vertical longitudinal section thereof, taken on the correspondingly numbered line in Fl 52.

Figure 4 is a vertical transverse section of the same. Figure 5 is a fragmentary hori zontal section on an enlarged scale, taken on line 5-5, Fig.1, and showing the manner in. which the blade or knife is engaged with one or the other cutting surfaces of the, sharpening tool. Figure 6 is a perspective view of a pair of blades orsharpener sec tions which together form the sharpening member of the tool. Figure 7 is a fragmentary longitudinal section of one of the sharpening blades, on a greatly enlarged scale, for the purpose of showing the form of the cutting teeth, ribs, ridges, or corru gations. y Similar characters of reference refer to like parts throughout the several views.

The holder of the knife sharpener is preferably constructed of a bar 10 of wood which i is substantially rectangular in cross section and of sufficient length so that the end 11 thereof will serve as the handle of the tool, while the other end 12 forms the shank upon which the sharpening devices are mounted,

Specification of Letters Patent.

Patented May 23, 183

of each notch has its rear part 16 arranged parallelwith the corresponding inner side 15, while the front part 17 of this outer side is inclined relatively to the companion rearpart thereof, so that the narrow rear part of this notch forms a seat which is of rectangular form in cross section and the front inclined part l'Z' of the outer side forms a guiding surface against which the knife blade 18 may be rested during the operation of sharpening the same. In each of these notches is arranged a sharpening blade 19 of steel or other suitable material.

which blade preferably has a plain inner or rear surface 20 while its outer or front surface is constructed to form a cuttingsurface over which the edge of the'knife blade may be drawn for sharpening the same. Each of these sharpening blades has its rear end engaged with the narrow rear part of one of the notches which forms a seat therefor, so that the rear side ofthe blade engages with the transverse inner side of the respective notch and the front part of the opposite or cutting; surfaceof the blade is arranged opposite the inclined guiding surface 17 of the respective notch, as best shown in Figs. 1 and 3. i y

The two sharpening blades or sections which together constitute the cuttingele ment of the knife sharpener are held in their respective notches by means which are so constructed that they hold both blades in place at thesame time, and thereby simplify the construction of the tool and also effect a considerable economy in the manufacture of the same.

In its preferred construction this fastening device comprises a front washer 21 i which engages with the front ends of both sharpening blades, a rear washer 22 seated in a recess 23 formed in the opposite or rear edge of the holder bar and a rivet 24% extending transversely through the partltion which separates the notches and engages its opposite enlarged ends with the outer sides of said washers.

During the operation of sharpening a knife the blade of the same is alternately drawn lengthwise through the spaces between opposite cutting surfaces of the blades and the inclined guide surfaces of the holder bar, during which operation the blade is rested in a transversely tilted position against these guide surfaces so as to produce the aroper bevel upon the cutting edge of the blat e. This operation is repeated as often as necessary to produce the desired cutting edge on the blade of the knife.

The cutting surface of each sharpening blade is preferably produced by means of a plurality of parallel cutting teeth, ribs, ridges or corrugations 25 which are arranged on the front side or outer surface of each sharpening blade, the arrangement of these teeth being such that they stand at an obtuse angle relative to the direction in which the knife is drawn past these teeth during the sharpening operation or in other words, the same lean in the same direction in which the knife is drawn when sharpening the same. By this arrangement of the teeth the cutting action of the same will not be too pronounced and still a sufficient shearing action of the same is obtained on the metal of the knife blade which will produce a sharpening effect on the same, thereby producing a sharpening effect without undue loss of metal and wearing down the knife blade unnecessarily.

In order to further reduce the cutting effect of these teetlneach tooth is so constructed that its front side or face 26 is arranged at an obtuse or steep angle relative to the direction in which the knife blade is to be sharpened is drawn past the same. while the rear side or face 27 of each cutter tooth is arranged at an acute or flat angle relatively thereto, as best shown in Fig. 7. By this means a rearward movement of the knife blade relative to the sharpening surface of each sharpening blade will have no sharpening effect on the same. but upon drawing the knife blade forwardly past the cutter teeth while in engagement therewith the outer edge or corner of eachsharpening tooth will produce a mild sharpening or abrading action upon the knife blade which will sharpen the latter without liability of the tooth digging into the metal of the knife blade and unduly wearing the same or producing a roughened surface thereon which otherwise would be the case.

In order to enable the sharpening of the knife blade to be effected by drawing the knife blade in thesame direction against both sharpening surfaces of the sharpening blades, the cutting teeth, ribs or ridges of the two sharpening blades which face in opposite directions, are arranged to slope or incline in the same direction and preferably at the same angle. as best shown in Fig. ll. By this means either or both sides of the knife blade can be sharpened by drawing the blade from the front side of the sharp-- cner toward the rear side of the same. thus avoiding improper use of the tool whilc sharpening a knife blade.

Each of the sharpening blades is prcl'ci' ably narrower than the holder bar and lhc sameis arranged in itsrcspectivc notch in the holder midway between opposite sh les ll icrco l so as to form

pockets

28,28 in the notches adjacent to the opposite longitudinal edges of each sharpening blade as shown in Figs. :2. ti and By this means a clearing space is furnished at opposite edges of each shar ening blade into which are discharged the small cuttings, metallic dust or chips re moved from the knife blade which is liLii]!.'.' sharpened. which chips in the absence of such provision would be liable to (flog lhc teeth of the sharpening blades and reduce their efficiency.

As a whole this knife sharpener is very simple and inexpensive in construction and permits of eliiciently and quickly putting :1 keen edge on a knife blade by simply drawing the edge of the same one or more times past the surfaces of the cutting blades in the manner described.

I claim as my invention 1. A knife sharpener comprising a holder bar which is provided on one side with a laterally opening notch and on its opposite side with a recess. a sharpening blade sealed in said notch, a washer engaging with the outer end of said blade. a washer sealed in said recess, and a rivet passing through said bar and connecting said 'ashers.

2. knife sharpener c'on'iprisiug a holder bar having two laterally opening nolchcs arranged side by side and separated by an intervening partition, sharpening blades seated in said notches, and a fastening dcvice engaging the outer ends o l both of said blades and extending into said partition.

A knife sharpener comprising a holder bar having two laterally opening notches arranged side by side and separated by an intervening partition, sharpening blades seated in said notches, and a fastening device extending through said partition and engaging with the outer ends of said blades and with that side of said bar opposile to the notches thereof.

M ARTIN T. GR A. F

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