US1678698A - Knife sharpener - Google Patents

Description

July 31, 1928.

G. A. GRAVES KNIFE SHARPENER Filed May 24, 1926 INVENTOR.

Patented July 31, 1928.

PATENT OFFICE.

lKNlfFE SHARPENER.

Application filed May- 24, 1926. Serial No. 111,276.

This invention-relates to-knife Sharpeners and-has for.its object to provide a cheapand effective device :for' sharpening. knives which may be readily employed. for'the purpose of giving a' sharp evenly beveled i, edge to the blade of the same. .It.is espserially-adapted for domestic 'use and .may .be affixed .to table orbench so -as tor-always be handy.

The device is so 1 made .as to be compact, durable .and inexpensive, sand is preferably a unitary device :made froma single stamping of-sheetsteel which is.-afterwards hardened-so as tormake.itrhardenoughito. sharpen most Ekni-ves.

In theacco mpanyingdrawings, forming a part ofthisgpecificat-ion, in which similar reference characters indicate 7 corresponding partsin the figures:

Fig. '1 i is. a;.perspecti-ve .viewof' the sharp- :ening: device affixed .to a portion .of a table, and sillustrating I lJl16'.Cl/V-l6 in use,-. the knife =-being indicated. in brokendines;

.Fig. 2 is aipl aneviewof the same and -;3 .is :.-an end -elevation j including a -blade-with.al knife in sharpeningpo'sition.

Referring .to ;the:dr.awings, 1 designates generally the .base i of :the device, which .is *here'shownwasfhaving a flat-surface or base portion 2 from which the-.bent up sharpening membersB :are struck, .forwex-ample, by a punching 01' stamping operation. .It is preferable to have the base portion 2 somewhat spaced from the table in order that the knife being sharpened is kept far enough away from the table so as to avoid any chance of marring it, and also to give room for fingers of the person holding the knife. This may be effected in any suitable way, but, for example, it may be done as I have here illustrated the device in the figures in which the base 1 has side walls 4, two of which terminate in the outwardly bent side portions 5 in which are punched holes 6 by which the device may be held to the table or bench by screws 7 as shown in the figures.

The sharpening members 3 are arranged in rows with the edges of one row overlapping the edges of an adjacent row so as to form between each pair of members 3 one of a series of aligned but spaced notches. It will be seen from the other figures, however, that these are not true notches since each opposing but staggered pair of members is somewhat spaced from the other. This feature of the device allows the knife to gradually assume a lower position as the sharpening is repeated and the members 3 wear without allowing the edge of the knife to encounter any metal surface which tends to dull it. It will be clear from the figures that in sharpening a knife it is drawn back and forth along the line as indicated in dots in Fig. 2

so that one side of the knife is presented to one row of sharpening members, and the other side of the knifeis presented to a: second row of sharpening members. It will be seen that the cutting members 3 are illustrated :as being parallel to each other and that the planes .of the fiat sides of the same meet the edges 3? and with them form ta vsharp cutting edge or corner, the planes of theflat sides and the planes of the edges3 both being oblique to the line of travel of the knife when it is drawn back and forth as it is being sharpened. Thus each member 3 has but one cutting edge or corner. "I prefer that the flat sides of the members 8 and the flat edges of the same each form an angle the sharpening members oneach side ofthe knife as I have shown, though I do not, of course, confine myself to so large a number on either side. It is essential, however, that there be a sufficient number so that the knife is always presented in the same aligned position. The lack of this feature has been the cause 'of failure of many previous knife sharpeners in the art. that is, they have not been foolproof and whether or not good results have been achieved has depended largely upon the skill and manipulations of the operator.- This device is entirely free from any such limitations for it is selfaligning. It is only necessary that the plane of the blade of the knife be approximately at right angles to the base 2 of the device and that the knife be allowed to contact with all the cutter members as it naturally will in normal use when the blade is drawn back and forth. When the knife to be sharpened is held in this way, the sharp edges of the members 3 in contact with the knife tool off minute chips from the edges of the knife and also tendto burnish and smooth the same. This results in giving the knife an excellent'cutting edge for domestic purposes such as paring. etc. In the course of time as the cutting edges of the members 3 gradually wear away, the knife tends to drop lower and lower between the rows of the members 3, though the life of the device when properly hardened is such that it lasts a long time. In this way as the members 3 wear and the knife drops lower, a new or unused portion of the sharpening edge of each member 3 is presented and becomes available for sharpening purposes, thus in use the knife sharpener retains its original efiiciency.

It will be seen from the above description that the device as shown and described is unitary, and I prefer to have it so. In fact, therein lies its cheapness and strength. The metal used for the same is preferably a medium carbon steel which, in the soft state, can be readily punched or stamped and then can be hardened by merely heating to a temperature of, say, 1500". F. and then quenching in water.

Having described my device, what I claim and desire to secure by Letters Patent is:

1. A knife sharpener adapted for domestic use comprising overlapping rows of fixed projecting sharpening members arranged substantially parallel with each other and each having a single cutting edge adapted to present between said rows a series of aligned sharpening apertures to the opposite sides of a knife drawn between the aligned working edges of each of said rows, each of said edges being formed by the intersection of planes oblique to the line of the sharpening apertures, and a base member adapted to hold said members in fixed relation.

2. A knife'sharpener adapted for domestic use comprising overlapping rows of fixed projecting sharpening members arranged substantially parallel with each other and each having a single cutting edge adapted to present between said rows a series of aligned sharpening apertures to the opposite sides of a knife drawn between the aligned working edges of each of said rows, each of said edges being formed by the intersection of planes oblique to the line of the sharpening apertures, and a base member integral therewith adapted to hold said members in fixed relation. I I

3. A knife sharpener adapted for domestic use comprising rows of fixed overlapping cutter members struck-up from within the margins of a baseportion, the adjacent hardened working edges of which are oblique to and adapted to sharpen'a knife drawn between said edges, said cutters forming adjacent andbetween their overlapping edges a series of aligned sharpening apertures adapted to impart a sharp beveled edge to said knife, each of said sets being formed by the intersection of planes oblique to the line of the sharpening apertures.

4:. A knife sharpener adapted for domestic use comprising rows of fixed overlapping cutter members struck-up from within the margins of a base portion, the adjacent hardened edges of which are adapted to sharpen a knife drawn between the same, said cutters forming adjacent their overlapping members a series of aligned sharpening apertures adapted to impart asharp beveled edge to said knife, each of said sets being formed by the intersection of planes oblique to'the line of the sharpening apertures, said members being parallel to one another and having cutting faces oblique to the line of said apertures.

GEORGE A. GRAVES.

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