US2089619A - File and method of making the same - Google Patents

Description

Aug T10, 1937. l. s. RlPLE'Y 2,089,619

FILE AND METHOD OF MAKING THE SAME Filed Nov. 27, 1955 2 sheets-sheet 1 Aug@ m9 1937. I. s. RIPLEY 2,089,619

FILE AND METHOD OF MAKING THE SAME Filed Nov. 27, 1935 2 Sheets-Sheet 2 @i /jza /JL l., IMI' "l" I I III Patented Aug. 10, 1937 UNHTED STATES PATENT OFFICE FILE AND METHOD F MAKING THE SAME Application November 27, 1935, Serial No. 51,960

13 Claims.

This invention relates to les and more especially to double-cut les and methods of making them.

The general object of the invention is to provide novel and improved files of this and similar types and also to provide new methods of file manufacture whereby such les may be easily and economically produced either by hand or by the employment of suitable machinery.

A more particular object of the invention is the provision in a double-cut le of teeth of novel configuration which render the file more efficient in operation and more adaptable in its utilization in connection with shaping various kinds of material.

g3 noticeable in working on bronze, brass, and other so-called greasy metals and are also in evidence in cutting and shaping cast iron, tool steel and other materials.

A further object of the invention is to provide a file of novel construction which will remove the material from the work in the form of shreds instead of chips as in the case of an ordinary file of the present standard manufacture. Such shreds do not ll up nor clog the throats between the teeth as rapidly as do the chips removed by means of the conventional double-cut illes.

In all of its preferred embodiments, my invention contemplates the provision, in the approximately diamond-shaped or lozenge-shaped teeth 0 of the double-cut files, of relatively slight grooves or scorings extending in the general direction of the axes of the les. IIhese scorings or flutings appear plainly upon the backs of the teeth and also modify the effects of the over-cut and up-cut 15 so as to produce entirely new and improved types of cutting edges. These scorings may be applied to the le blank at different stages in the manufacture of the les as will be fully disclosed as ,o the description proceeds.

Other objects and features of novelty, both with respect to the novel files and to their methods of manufacture, will be apparent from the following specification when read in connection with the accompanying drawings in which certain embodiments of the present invention are illustrated by way of example.

In the drawings:

Figures 1-3 inclusive illustrate in various ways certain steps in the manufacture of a double-cut le in accordance with present practices; Figure 1 showing in plan a file blank which may be considered to have been ground and draw-filed preparatory to cutting the teeth; Figure 2 a plan View of the blank, showing diagrammatically the appearance of the le after over-cutting; Figure 2A a greatly enlarged fragmentary sectional view of one surface of the file taken on a line at right angles with the over-cut; Figure 2B a similar View indicating the general appearance of the le surface after stripping the over-cut; and Figur-e 3 showing somewhat diagrammatically the appearance of the file in plan after the superposition of the up-cut upon the over-cut;

Figures 4 7 inclusive similarly illustrate various stages of the manufacture of a double-cut file in accordance with one embodiment of the present invention; Figure 4 being a plan View of the ground and draw-filed blank similar to Figure 1; Figure 5 being a plan view of the blank having the over-cut applied thereto as in Figure 2; Figure 6 a diagrammatic plan view of the over-cut blank with the scorings or grooves superposed thereon; Figure 6A a fragmentary greatly enlarged sectional view of the file surface as indicated in Figure 6, taken on a line at right angles to the direction of the over-cut; Figure 6B a plan view on the same scale of a portion of the le blank indicating the appearance of the surface of the file after the application of the grooves or scorings to the over-cut somewhat more accurately than the diagrammatic showing in Figure 6; Figure 7 a diagrammatic plan view on the same scale as Figure 6, showing the finished file after the up-cut has been applied to the scored overcut surface; and Figure 8 is a somewhat diagrammatic plan view on an enlarged scale of a portion of a completed ille such as shown in Figure 7;

Figures 9-12 inclusive are views similar to those in the preceding descriptions illustrating another embodiment of the present invention; Figure 9 being a plan view of the uncut blank as in Figures 1 and 4; Figure 10 a diagrammatic plan View showing the blank scored or grooved; Figure 11 a similar diagrammatic view showing the scored blank with the over-cut applied thereto; and Figure l2 a diagrammatic plan view of the finished le with both the over-cut and the up-cut applied to the previously scored blank;

Figure 13 is a view in perspective illustrating the operation of scoring or grooving the le blanks; and

Figure 14 is a View in transverse section of the scoring tool shown in Figure 13.

In order to particularly point out the present invention and to distinguish it from the ordinary double-cut files and the conventional methods employed in their manufacture, a short exposition of the prior art will be set forthfin connection with the first few figures designated with the legends Prior art in the drawings annexed hereto. arermade are sheared from the metal sheets or bars and are then forged and finally carefully and uniformly annealed. Then the surfaces of the annealed blanks are ground. After this, the blanks are finished by means of draw-fllingin order to remove any unevenness left on the surface of the flle by the grindstone. In- Figure 1 the reference numeral I indicates generally the plain le blank at this stage of the process of manufacture, the blank being provided with the usual tang Il. The draw-filing process may be done either by hand or by suitable machinery which automatically reciprocates a file of the proper construction longitudinally of the blank. After this operation, the over-cut is applied as indicated at l2 in Figure 2 of the drawings,l usually by means of a broad chisel of special configuration.y This over-cutting operation produces the preliminary ridges or teeth M of the file blank each having a sharp edge or burr l5, a front surface or rake I6 and back or clearance Il, as shown in the enlarged' fragmentary view of Figure 2A. In the usual method of manufacture, the next step is stripping the over-cut, which is accomplished by reciprocating a le across the surface of the blank in the same Way as in theV initial draw-filing. This' serves to remove the sharp edges or'burrs I5 of the teeth'as shown at I8 in Figure 2B of the drawings. Then the upcut is applied to the blank as indicated at I9 in Figure 3 of the drawings'. This operation serves to break up the long-ridges I4 comprising the initial teeth of the le into intersecting series of small substantially diamond-shaped teethlor scallops having converging cutting edges, as shown at 20 in Figure 3. It will be noted that the angle the up-cut makes with the axis of the file is considerably smaller than that of the over-cut.

With this rsum of the prior art, the description of my improved files and their methods of manufacture'will be readily understood. One of the most efficient embodiments of the'invention is illustrated in various stages of manufacture in Figures 4-7 inclusivefof the drawings. Figure 4 illustrates a blank 25 in the same state as Figure 1 after it has been ground and draw-filed. In Figure 5 the blank' 25 is represented as having applied thereto the over-,cut l2 and corresponds exactly to the stage represented in Figures 2 and 2A illustrating the prior art. Y

At this point, instead of stripping or again draw-ling the blank as shown in Figure 2B of the prior art disclosure, the sharp edges I5 of the preliminary teeth l5 are permitted to remain. Then the file blanks 25 having the over-cut I2 thereon are scored along a multiplicity of parallel lines extending generally in the same direction as the axis of the file.Y These lines are preferably parallel and the spacing'therebetween may vary within rather wide limits, but the striations or grooves should preferably be close enough together so that several of them take eiect on each of thesubsequently formed scallops ordouble-cut Ordinarily, the blanks from which the files aosae 19 teeth. The depth of these grooves 2T is readily appreciable with the naked eye kand should not be confused with the minute scratches which are Y .or mechanically. Preferably the grooves are formed in the blank by means of a tool such as the one illustrated at 30 in Figures 13 and 14 f which is of triangular cross-section having the three cutting edges 3| each provided with a series f of triangular teeth or serrations 32 corresponding to the shape and spacing ofV the grooves desired on the file. In order to attain uniformity a preferred manner of execution of this step in the process is to place the iile blanks upon the bed of a machine similar to those employed in draw-iiling the blanks and securing the tool Sil upon a reciprocating carrier similar to that used in the draw-filing'operation. The tool is drawn back and forth across the surface of the file until the scoring Z'I'is of the proper depth, in most cases this depth being, as already indicated, less than that of the over-cut or the up-cut which determines the height of the teeth.

Other possible ways-l of cutting the grooves will suggest themselves to those skilled in the art, and may include the use of straight or circular knurling tools, a special presser foot attached to the cutting machine, an artificial abrasive tool, or an artificial abrasive grooved wheel, or in fact by the use of any type of machine which employs a reciprocating tool or work carrier. Y Y

An approximation of the actual ap-pearance of the cutting surfaces of the le shown diagrammatically in Figure, 6 is presented in Figures 6A and 6B. In Figure 6A the grooves l2i appear in the tops of the single-cut teeth i4 and also pass through the front face or rake of each tooth. The scorings or grooves 2l extend along the backs or clearances il of each tooth for a distance which depends upon the depth of cut of the grooves. It must be realized that the teeth as actually formed by this operation will not be so geometrically perfect as suggested by the illustration in Figure 6A, but during the scoring process not only will some of the metal be cut away from the teeth, but other portions of the surface will be distorted and caused to ow and burrs will be formed adjacent the edges of the grooves 27. A fragmentary plan view of the'preliminary roughened teeth formed by the over-cut l2 and the superposed grooves 21 is shown in Figure 6B, which is also in somewhat diagrammatic form.

' The next operation comprises applying the up-cut I9 to the file blank. This serves to break up the elongated, serrated single-cut teeth VI4 into a multiplicity of intersecting series of lteeth or scallops 35 which have ingeneral outline the typical configuration of the scallops 2i] of the conventional leof the same grade. However, as will be clearly seen from the enlarged View shown in Figure 8, each of these teeth is longitudinally striated, the cutting edges are serrated and their backs scored by the lines which remain from the cutting of the grooves 27 after the application of the up-cut i9. Naturally the up-cut I9 causes the metal of each tooth formed to flow together somewhat and has the effect of not only closing or partially obliteratng portions of the over-cut, but also altering the-regularity of the scorings or grooves 21.

It will be noted that the actual appearances of the teeth as shown in Figure 8 are quite diierent from the regular, unbroken scallops formed by the conventional methods, and that this difference is reflected rin greater eiciency, accuracy, and economy in the utilization of the new le. The spacing of the grooves 21 in most cases is different from the transverse spacing of the intersections between the over-cut and the up-cut so that the actual shape of the finished teeth in lsuccessive rows along the file diers considerably. Some teeth will be intersected at their apexes by one of the scorings 21 while others will be provided with score lines upon the tapering side edges thereof, the cutting points remaining as narrow, chisel-like edges.

Another embodiment of the invention is illustrated in Figures 9-12 of the drawings and shows the eiect of applying the striations or scorings prior to both the over-cutting and up-cutting of the blanks. As before, the blank designated 40 in Figure 9 of the drawings has been ground and draw-filed preparatory to cutting. In Figure 10 the blank 4|] has been scored as at 21 directly after it has been smoothed by the draw-filing operation. In Figure 1l the over-cut l2 has been applied over the scorings 2l and finally, as shown in Figure 12, the up-cut I9 has been applied. The teeth 45 in this ligure are of similar general outlines to those shown at 35 in Figure 7 but are somewhat more sharply defined along the right-hand edges due to the over-cut having been applied after the scoring. The file produced by serrating the blank rst, then overcutting and up-cutting is equally as eiective as the one produced by serrating after the overcut and prior to the up-cut.

For certain other purposes, it may be desired to apply the scoring to the file after both the over-cut and up-cut have been applied and this method and resulting article comprise still another embodiment of the present invention.

From these disclosures, it will be realized that by means of the present invention there have been provided novel and improved files and methods of producing them which attain the stated objects in an eicient and economical manner; the principles of the invention being applicable to double-cut files of various degrees of neness.

It is understood that various changes and modifications may be made in the embodiments illustrated and described herein without departing from the scope of my invention as defined by the following claims.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. The method of making a double-cut le, which includes in combination with the teethcutting steps, the step which comprises forming in the metal of the working surface of the le a series of shallow grooves, said grooves extending substantially in the direction of the longitudinal axis of the le and being of less depth than the height of the teeth whereby the resulting over-cut and the up-cut, and of less depth than either of said over-cut or up-cut.

3. The method of making a double-cut le, which includes in combination with the application of the over-cut and the up-cut, the step which comprises forming in the working face of the le a series of narrow, shallow, substantially parallel, closely adjacent scorings extending at an angle to both the over-cut and the up-cut, and of a depth of the order of magnitude of approximately one-third of the depth of the overcut.

4. The method of making a double-cut file, which comprises the steps of scoring the blank along a plurality of spaced lines extending substantially in the general direction of the axis of the blank, then applying the over-cut, and then applying the up-cut, the scorings being of less depth than either the over-cut or the up-cut.

5. The method of making a double-cut le, which comprises the steps of applying the overcut to the blank, scoring the blank along a series of spaced lines extending in the same general direction as the axis of the blank, and then applying the up-cut, the scorings being of less depth than either the over-cut or the up-cut.

6. The method of making a double-cut le, which comprises the steps of,applying the overcut to the blank, scoring the blank along parallel, closely spaced lines extending in the same general direction as the axis of the blank, and then applying the up-cut, the scorings being of less depth than either the over-cut or the up-cut.

'7. The method of making a double-cut file, which comprises the steps of applying the overcut to the blank to form a series of temporary teeth of the single-cut type, then serrating the edges of said temporary teeth, and then dividing the serrated teeth thus formed into series of jagged double-cut teeth by applying the up-cut, the serrations being of less depth than said over-cut or up-cut.

8. The method of making a double-cut le, which comprisesythe steps of applying the overcut to the blank to form a series of temporary teeth of the single-cut type, then applying to the forward edges and backs of said temporary teeth serrations of a depth less than the depth of said over-cut, and then dividing the serrated teeth thus formed into series of jagged double-cut teeth by applying the up-cut.

9. The method of making a double-cut le, which comprises the steps of applying the overcut to the blank, then applying the up-cut thereto, and then scoring the file along a series of closely spaced, substantially parallel lines extending in the same general direction as the axis of the blank, the scorings being of less depth than either the over-cut or the up-cut.

10. A double-cut le having upon its Working face a plurality of intersecting series of raised scallops forming the substantially lozenge-shaped teeth of the conventional double-cut type, there being a plurality of generally longitudinally extending scorings on the working face of said file, the spacing of the scorings being without regard to the spacing of the intersections of the lines of over-cut and up-cut of said file, whereby the teeth of the le are non-uniformly serrated.

ll. A double-cut file comprising teeth having the conventional, forwardly convergent cutting edges thereon, there being a plurality of spaced scorings on said le, said scorings being of less depth than either the up-cut or the over-cut of the le, and the direction of said scorings being at an angle to both the over-cut andl the uncut, whereby both of the convergent cutting edges of said teeth are provided with serrations.

12. A le of the type described having interseating series of substantially pointedrteeth on its Working surface, therebeing sem-ations on the cutting edges and backs of said vteethlsad serrations being of less depth than the height of said teeth. v ,e

` 13. A double-cut file having upon its Working face a plurality of intersecting series of raised scallops forming the substantially lozenge-shaped teeth ofthe conventional double-cut type, the cutting portions of said teeth beingserrated, the serrations extending in the general direction of the length of the file. y Y n l IRA S. RIPLEY.

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