US2115778A - Scissors sharpener - Google Patents

Description

May 3, 1938. F. KRHENBUHL S'CISSORS SHARPENER Filed July a, 193e INYENTOR. /C/-e/Eoe/C/v/ /KQf//Zl ATTORNEYS Patented May 3, 1938 PATENT OFFICE Soissons SHARPENER Friedrich Krhenbuhl, Berlin-Charlottenburg,

' Germany, assignor to A. & F. Products, New York, N. Y., a partnership composed of Albert L. Stirn and Ferdinand R. Stirn Applicati July s, 1936, serial No. 89,559

3 Claims.

`This invention relates to an instrument adapted for sharpening edge tools and more particularly the class known as scissorsA Sharpeners.

One object of the invention is to provide a simple, neat and inexpensive article that can be used by anyone for quickly sharpening the blades of a pair of scissors, and which is capable of producing a fine cutting edge Without the use of abrasive materials.

Another object is to provide a scissors sharpener which may be used to sharpen any kind of scissors irrespective of their shape. i

Still a further Objectis Yto provideY ascissors Sharpener whereon the scissors edges always con,- tact the same place on the sharpening member.

A further object is to, provide a scissorssharpeer which will withstand friction between cutting edges of the scissors without the creationof ridges or grooves on the sharpening member which would tend to dull the `edges sought to be sharpened. Y

Further objects and advantages will become apparent as the specification proceeds and when taken in connection with the accompanying drawing which illustrates a preferred embodiment of the inventive concept together with modifications thereof.

In the drawing:

Figure l is a front elevation of a scissors sharpener according to the invention showing a portion broken away.

Figure 2 is an edge elevation.

Figure 3 is a side view of a pair of scissors showing the improved scissors Sharpener in two of the positions which it assumes during the sharpening operation.

Figure 4 is a cross-section along the line 4-4 of Figure 3.

Figure 5 shows a modification of a scissors Sharpener according to the invention.

In the manufacture of the preferred form of the invention, which is illustrated in the drawing, a round, smooth and highly polished pin of hard steel is inserted into a handle of hard rubber or some other composition so that it projects upward therefrom at an angle of approximately 60.

Scissors Sharpeners comprising fundamentally a handle and a pin protruding therefrom at an angle are admitted to be old in the art, but the present invention has been designed for the specific purpose of overcoming the disadvantages disclosed by these conventional articles.

In many of these conventional scissors sharpeners the pin or sharpening member is provided (Cl. 'Z6-82.2)

with at, substantially parallel sharpening surfaces. This construction disregards entirely the fact that the angle between the scissors blades changes as the pin or sharpening member is reciprocated between them, as shown in Figure 3 of the drawing. Therefore, the cutting edges of the scissors blades will not contact the entire surface during the reciprocation of the pin, but will more or less wobblef thereon, resulting in nicks and other damage to the sharpening surfaces.

As the cutting edge of the scissors blade does not contact the same spot on the sharpening surface of the pin during the sharpening operation, the edge will not be uniformly sharpened. Furthermore once the sharpening surfaces of the pin have been damaged, the article is rendered practically useless.v

This obstacle and disadvantage has been overcome by making the pin Orsharpening member perfectly` round so that thepoint of contact' between the cutting edges of the scissors blades is constant and thersharpening movement will be performed in a straight `continuous line.

Furthermorathe pin should be smoothand highly 'polished and madefof steel, agate orsome other lmaterial harder than the steel Vof the cutting edgesof the scissors. In this mannenthe jarring effect upon 'the cutting edges of the ccnventional scissors Sharpeners has been eliminated and ridges or nicks in the pin avoided.

It is also a practice to provide these conventional scissors Sharpeners with special means for supporting the sides of the scissors blade with the result that they may be used only for scissors of a certain shape or size. With a view to eliminate this disadvantage, the present invention has been so designed that the edge of the handle itself adjacent the scissors blades servesy as a guide for the upper interior corner edge of the outside blade and the lower exterior corner edge of the inside blade. In this manner the cutting edges of the blades are kept free and clear of the handle and may slide smoothly on substantially the same spot on the round surface of the pin. In other words, the aforementioned points will slide freely up and down on the edge of the handle when the pin is reciprocated regardless of the shape or size of the scissors.

Referring more particularly to the drawing l0 is a handle provided with a roughened surface Il to permit the Sharpener to be held easily between the fingers and the thumb of the operator. A pin I2 or sharpening member is inserted into the handle so that it projects upward at an angle of approximately 60. This pin as previously stated, is round, smooth and highly polished and made of hard steel, agate or other material harder than the steel of average scissors.

The handle is provided with a straight continuous edge I3 against which the points I4 and I5 of the scissors blades I6 and II rest during the sharpening operation.

The handle IU is preferably broader at its base than at the top so as to provide a more natural grip and thus indicate to operator how the pin should be inserted between the scissors blades.

In the modification shown in Figure 5, the handle or grip I0 is provided with a slot I8 in which the pin I2 is provided with an integral lever arm 20 which moves in the slot I8. The lever arm 20 may be provided with a handle 2l. The upper portion of the grip I0 is sector shaped, the pivot I9 serving as the center, so that the handle 2I may be moved freely along the posterior end of the slot I8. This modication permits the pin I2 to be folded into the handle or grip I 0 so that it may be carried by a person in his clothing. A stop 22 for the lever arm 20 is provided to insure a proper angle between the pin I2' and the grip I0.

The manner of use of the improved Sharpener is as follows:-

The sharpening apparatus is taken into the left hand vertically. The scissors are levelled in the right hand and the blades I6 and II are opened over the pin I2 and the cutting edges are then drawn across it, the scissors blades being pressed together at the same time.

During this operation the lbevelled sides of the scissors blades slide sideways along the edge I3 which serves as a guide. It is obvious that left handed persons should take the apparatus upside-down into the right hand, so that the pin I2 points to the left, downward.

What is claimed is:

1. A scissors Sharpener of the type which is drawn between the blades of the scissors, comprising the combination of a flat grip portion of plastic material having one unbroken vertical straight edge, a widened base and sucient height so that the device will be inproper position for use when the thumb is applied to one side and the first two ngers to the other side, a round,

smooth pin of material harder than the material sought to be sharpened, said pin being inserted into said grip portion through said straight vertical edge and projecting obliquely therefrom at such an angle that only the corner edges of the scissors blades will ride on said straight edge, said pin being highly polished and being centrally positioned in said edge to provide an equally divided and normal straight vertical guiding surface for the corner edges of the scissors blades whereby the edges of the blades of said scissors ride along said straight edge during the sharpening operation with the edges of the scissors to be sharpened being spaced substantially away from said straight edge.

2. A scissors Sharpener of the type which is drawn between the blades of the scissors, comprising the combination of a relatively iiat plate forming a grip portion having one unbroken vertical straight edge, a round, smooth pin of material harder than the material sought to be sharpened, said pin being inserted into said grip through said vertical edge and projecting obliquely therefrom at such an angle that only the corner edges of said scissors blades will lride on said straight vertical edge, whereby the edges of the scissors to be sharpened will be spaced from said vertical straight edge during the sharpening operation.

3. A scissors sharpener of the type which is drawn between the blades of the scissors comprising the combination of a grip portion having two opposite faces forming an intermediateV slot and a vertical edge, a sharpener member in the form of a bell crank pivotally mounted in said slot, the arm serving as a Sharpener member being adapted to project obliquely from said vertical edge when utilized, and the other arm serving as an actuator projecting through the opposite edge, whereby said sharpening member may be moved from an inoperative position to an operative position, said edge through which the actuator projects being circular to conform to the arc described by said actuator when the sharpening member is moved from an inoperative to an operative position and vice versa.

FRIEDRICH KRHENBUHL.

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