US2457714A - Knife sharpener - Google Patents

Description

Dea-2s, ma.' l W, R, PANCQAST 2,457,714

KNIFE SHARPENER Filed May l2, 1947 Patented Dec. 28, 1948 UNITED-'STATES PATENT OFFICE v KNIFE SHARPENER n William R. Pancoast, Evanston, Ill. Application May 12, 1947, Serial No. 747,427

8 Claims. 1

This invention relates toimprovements in a knife sharpener, and more particularly to a sharpening device for maintaining a cutting edge on knives and similar cutting implements that may be sharpened in the way a knife blade may be sharpened, although the invention may have` other uses and purposes as will be apparent to one skilled in the art.

In the past, many and various types of knife sharpeners have been developed, but in InoSt cases they have proven objectionable in that the operator is required to simultaneously perform a plurality of operations, such as both moving the knife blade and rotating the sharpening element, and in other cases these formerly known devices were objectionable in that they required skill on the part of an operator before good sharpening of the cutting instrument could be had. In other instances, devices of this character heretofore known failed to adequately sharpen a cutting implement at the base and tip of the blade, and most frequently were so costly in manufacture as to be prohibitively expensive to a great number of potential users. 1

With the foregoing in mind, it is an important object of this invention to provide an economical and yet highly efficient knife Sharpener, requiring practically no skill on the part of an operator to effect an extremely fine edge on the cutting tool being sharpened.

Another object of this invention is the provision of a sharpening device arranged to magnetically maintain the blade of a tool being sharpened at the proper angle to the abrasive element during the sharpening operation.

Still another feature ofthe invention resides in the provision of a simple form of sharpening device wherein the operator is only required to move the knife blade relatively to the cutting element of the device, and means are provided to guide the movement of that blade so that the operator may easily maintain the blade at a proper angle to the cutting element..

It is also an object of this invention to provide a simple form of sharpening device wherein both sides of the blade maybe brought to bear against an abrasive element while the device remains in the same position, and means are provided to adequately guide said blade at the proper angle to the element.

Still a further object of the invention resides in the provision of a sharpening device including an abrasive element, with wing members disposed one on each side of said element at an angle thereto, said wing elements either being magnetized or, if made of non-magnetic material, carrying a magnet on the outer face thereof.

Also an object of this invention is the provision of a simple form of sharpening device having an abrasive element that remains stationary during asharpening operation, the device being equipped with means, however, to adjust the position of that element periodically to equalize Wear of the abrasive surface of the element.

While some of the more salient features, characteristics and advantages of the instant invention have been above pointed out, others will become apparent from the following disclosures, taken in conjunction with the accompaning drawing in which:

Figure 1 is a side elevational View of a sharpening device embodying principles of the instant invention:

Figure 2 is an end elevational view of the device of Figure 1, taken from the right-hand side of Figure 1;

Figure 3 is a top plan view of the structure of Figures 1 and 2, also disclosing a knife in operative association with the device; and

Figure 4 is an enlarged fragmentary vertical sectional view through the device, with parts in elevation, taken substantially as indicated by the line IV-IV of Figure 2, looking in the direction of the arrows.

As shown on the drawings:

It will be understood that a sharpening device embodying principles of the instant invention may be made in several different forms, to be mounted in a wall bracket, held in the hand, laid at rest upon a table, etc. For purposes of illustration, I have selected a form of the device that may either be held in the hand during the sharpening operation, or laid at rest upon a table top and merely steadied with one hand, while the other hand of the operator manipulates the blade being sharpened.

The illustrated embodiment of the invention includes a handle l, which may be made of wood, plastic, o-r any other suitable material. The handle may have a cap 2 disposed over its inner end if so desired. Into the end of the handle a bolt 3 is threadedly engaged and the protruding end of that bolt may be covered with a suitable decorative cap 4 if so desired. This cap, of course, is in the form of a nu-t and may be tightened down upon the bolt either with the fingers of the operator or with a suitable implement such as a wrench.

Carried on the bolt 3 is an abrasive element 5 which preferably is any suitable form of element having grinding faces on opposite sides thereof. In the illustrated instance the element is shown in the form of an abrasive wheel, although with the particular embodiment of the invention disclosed in the drawings, the wheel remains stationary during use of the device for sharpening purposes. Embracing the lower portion of the wheel is a substantially U-shaped member E, and when the legs of this member are clamped against the abrasive element 5 by tightening the cap nut 4, the element is held sufficiently securely to remain stationary during a sharpening operation. However, the element 6 has Van opening 1 in the bottom thereof to facilitate grasping the abrasive element 5 and forcefully rotating it periodically to equalize Wear on the grinding faces of the element.

With reference more particularly to Figure 5, it will be noted that the upper portion of the legs of the member 6 are divergent to provide a pair" of wings 8 and 9 on opposite sides of theabrasive element 5 and disposed at an angle tothat abrasive element. Preferably, these wings are flat so as to present inside faces that vmay lbear flatly against a knife blade such as the blade I0 seen in Figure 3 and thus provide a positive guide for the blade during a sharpening operation. Each of the Wings 8 and 9 is preferably disposed at an angle of between 15 and 30 to the adjacent grinding face of the abrasive element, and for most household knives, an angle of 20 is very satisfactory.

In use, the present invention is so simple that even the most unskilled operator can effectively and adequately sharpen a knife or other cutting implement. It is simply necessary to hold the handle l in one hand, or as an alternative course the device upon a table with the bottom of the element 6 and the outer end of the hand contacting the table, and then place the knife bl-ade flatly against one of the wings 8 or 9 with the cutting edge of the blade in contact with the abrasive element, and draw the blade toward the operator the full length of the blade. Then, the operation is repeated with the blade in flat contact with the other Wing 8 or 9 so that the other side of the cutting edge is brought into contact wih the abrasive element. A few strokes of the blade in this manner, the number of strokes depending of course upon the original condition of the cutting edge of the blade, is usually sufficient to provide an extremely keen cutting edge on the blade.

Now, to further facilitate the sharpening of a knife or other implement by a most unskilled operator, magnetic means may be employed to attract and maintain the blade in the proper posi-f tion during the sharpening operation. To this end, if the U-shaped or yoke member 6 is made of magnetizable metal, the entire member may be in the form of a horse-shoe magnet so that each having grinding faces on opposite sides thereof,

wing 3 or 9 will effectively attract the blade and@ hold it flatly thereagainst at the proper angle for sharpening, and the resistance to an adverse canting of the blade provided by the magnetism will most frequently be sufficient to resist anym tendency of the operator to misalign the blade.

If it is deemed too expensive in manufacture to provide the element B in the form of a horse-shoe magnet, that member 6 may be made of any suit able economical and non-magnetic material. When made of such material, it is a simple eX- pedient to attach a bar magnet to the outer face of each wing S and 9 by brazing, soldering, or some equivalently simple operation. In the illustrated showing I have provided a bar magnet ll on the wing 8 and a similar magnet l2 on the outer face o-f the wing 9. The magnetic action set up by these magnets l l and l2 is amply sufficient to operate through the relatively thin wing 8 or 9 and tend to forcefully hold the blade at the proper inclination. Obviously the wings 8 and 9 may be apertured and the magnets set in for direct contact with the blade, if so desired.

It will be especially noted that the entire structure is highly simple in character, very economical to manufacture, easy and most effective to use a support for said element, and a pair of diverging magnetized plates disposed one on each side of said element to hold a knife blade at the proper angle to said element during sharpening.

- 2. In a knife Sharpener, an abrasive element, and a Wing member disposed at an angle to said element to bear against a knife blade and hold the same at the .proper angle for contact With said element, and a magnet carried by said wing member to attract a knife blade fiatly against said wing member.

3. In a knife Sharpener, an abrasive element, and magnetic means disposed at an angle to said element to attract and maintain a knife blade at the proper angle to said element during sharpening.

4. In a knife sharpener, an abrasive element, and magnetic means disposed at an angle to said element 'to attract and maintain a knife blade at the proper angle to said element during sharpening, said means being at an angle between 15 and 25 to said element.

5, In a knife Sharpener, supporting means, an abrasive element having grinding faces on opposite sides connected vto supporting means, a U- shaped member embracing the lower part of said element and connected to said supporting means, the legs of said member diverging in their upper portions to provide guide faces at an angle to said grinding faces for a knife to be sharpened, and magnetic means associated with the legs of said member to attract a knife blade flatly against either of said guide faces.

6. In aknife Sharpener, supporting means, an abrasive element carried thereby, and a horseshoe magnet member v'embracing vsaid element from beneath and carried by said supporting means, the legs of saidmagnet flaring outwardly in the upper portions to attract and maintain a knife blade at an angle to. said element during sharpening.

' 7. In a knife Sharpener, ari-abrasive element, a guide member `adjacent said element and disposed at'an angle thereto, supporting means for said element and guide member, and a magnet carried by said member to attract a knife blade flatly against said guide member to maintain the blade at the proper angle'tosaid abrasive element.

8. Ina knife Sharpener, an abrasive element, a guide member adjacent said element and disposed at an angle thereto, supporting means for said element and guide .memben said member being magnetized.

'WIILIAM R. PANCOAST.

REFERENCES ACITED The following references are of record in the

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