US3015239A

US3015239A - Sharpening and filing apparatus for serrated cutting edges

Info

Publication number: US3015239A
Application number: US55250A
Authority: US
Inventors: William F Just
Original assignee: Individual
Current assignee: Individual
Priority date: 1960-09-12
Filing date: 1960-09-12
Publication date: 1962-01-02
Anticipated expiration: 1979-01-02

Description

W. F. JUST SHARPENING AND FILING APPARATUS FOR SERRATED CUTTING EDGES Filed Sept. 12, 1960 m M 3 m km W a w 2H 5/ Mum/w EJc/Si' United States Patent Ofiiice 3,015,239 Patented Jan. 2, 1962 3,615,239 SHARPENING AND FILING APPARATUS FOR SERRATED CUTTING EDGES William F. Just, 3860 Region Ave., Robbinsdale, Minn. Filed Sept. 12, 196i}, Ser. No. 55,250 8 Ciaims. (CI. 76-36) This invention relates to apparatus for use in filing serrated cutting edges and more particularly to apparatus for use in filing and sharpening the teeth of saws.

An object of this invention is to provide a novel saw filing apparatus, of simple and inexpensive construction, for use in filing saws.

Another object of this invention is to provide a novel and improved saw filing apparatus including a file holder arranged and constructed to support a file in predetermined relation with respect to the teeth of a saw to permit ready and accurate filing and sharpening of the saw teeth.

A further object of this invention is to provide a novel and improved saw filing apparatus including the file holder having a plurality of pairs of file-receiving apertures arranged to receive and support a file in a plurality of predetermined positions with respect to oppositely angled teeth of saws to permit ready and accurate filing of difierent types of saw blades.

These and other objects and advantages of my invention will more fully appear from the following description, made in conection with the accompanying drawings, wherein like reference characters refer to the same or similar parts throu hout the several views, and in which:

FIG. 1 is a top plan view of my invention with certain parts thereof broken away for clarity and illustrated in the different position by dotted line configuration;

FIG. 2 is a side elevational view of my invention;

FIG. 3 is a cross-sectional view of my invention taken approximately along line 33 of FIG. 1 and looking in the direction of the arrows;

FIG. 4 is an enlarged fragmentary longitudinal section approximately along the center line of FIG. 2 of my invention illustrating details of certain parts thereof; and

FIG. 5 is a cross'sectional view taken approximately along line 5-5 of FIG. 1 and looking in the direction of the arrows.

Referring now to the drawings, most specifically to FIG. 1, it will be seen that one embodiment of my saw filing apparatus, generally designated in its entirety by the reference numeral 1%, includes a substantially U- shaped file holder 11, preferably constructed of a rigid metallic material. This channel-shaped file holder 11 includes a bight or web portion 12 having a pair of spaced-apart legs 13 and 14 integrally therewith and depending therefrom.

i It will be noted that each of the legs 13 and 14 of the channel-shaped file holder 11 is provided with a plurality of longitudinally spaced, triangular-shaped recesses or apertures as best seen in FIGS. 1 and 2. These apertures are arranged in opposed pairs, the pairs designated by the

reference numerals

15, 16, 17 and 18. Referring now to FIG. 2, it will be seen that all of the apertures are of substantially identical size and shape but that the apertures comprising each pair are longitudinally offset with respect to each other. Actually each pair of apertures is adapted to receive the file therein as best seen in FIG. 1 to correctly position the file with regard to teeth of the saw to be filed. It will also be noted that the pair of apertures 15 are longitudinally offset oppositely of the pair of apertures 16 while the pair of apertures 17 are longitudinally offset oppositely from the pair of apertures 18. Actually the pairs of apertures 15 and 16 comprise a set of file receiving apertures for filing the oppositely angled teeth of a conventional crosscut hand saw. The pairs of apertures 17 and 18 comprise a set of file receiving aperturesfor use in positioning a file for filing and sharpening the oppositely angled teeth of a conventional rip saw.

In this connection, the leading or cutting edge of a rip saw more closely approaches the vertical than the teeth in a cross cut saw, while the trailing edge of the teeth in both the rip and the cross cut saw is disposed at an angle with respect to the vertical. it will also be noted that while the actual cutting edge of each tooth in both the rip and cross cut saw is disposed in parallel relation but oppositely beveled with regard to the next adjacent tooth which permits the teeth to not only shear but to remove the sheared material to thereby form the kerf. Because of the angulated relation or opposite beveling of each adjacent tooth, I have arranged the pairs of apertures into sets as pointed out above.

Referring again to FIG. 2 it will be seen that a file P, which is of triangular cross section configuration, will be positioned and wedged into the lowermost portions of each of the recesses or apertures when the file is disposed in seated relation therewith. In order to provide the proper seating and angulation of a file within a pair of apertures, each of the apertures comprising a pair are similarly oriented with respect to each other while the other pair of a set is differently arranged with respect to its associated pair. In this connection it will be noted that the pair of apertures 15 are defined in part by sides 15a and 15b against which the sides of the file F are abutted. However, the sides 15a and 15b each of the apertures comprising the pair 15 are similarly oriented but are slightly longitudinally offset with respect to each other. The orientation of the sides 15a and 15b of the pair of apertures 15 may be referenced to the bight or web portion 12 of the file holder and it will be noted that the sides 16a and 16b of each of the apertures comprising the pair 16 are oriented similarly with respect to each other but are oppositely or differently oriented with respect to the sides 15a and 15b of the pair of apertures 15. Thus it will be seen that the apertures comprising each pair are similarly oriented but are offset longitudinally with respect to each other and are differently oriented with respect to the other pairs of that set or of a different set.

In this connection it will be noted that the sides 17a and 17b which define in part the apertures of the pair 17 are similarly oriented with respect to each other but are differently oriented with respect to the sides 18a and 18b which define the apertures 18.

Means are provided for releasably retaining the file F in seated relation within pair of apertures and this file-retaining mechanism 19 includes a substantially flat file-engaging member 26*, preferably formed of metallic material and having a threaded board 20a formed at one end thereof. Referring now to FIG. 4 it will be seen that this file-retaining mechanism 19 is also provided with means for adjustably urging the file-engaging member 20 into engagement with file F and this means includes an elongate threaded screw 21 having an enlarged head 21a, the threaded shank of the screw threadedly engaging and extending through the threaded bore Ztla of the file-engaging member 20. In use the file retaining mechanism 19 is positioned between the legs or flanges 13 and 14 with one end thereof disposed in engagement with the bight portion 12. The screw 21 is rotated thus causing the opposite end of the file engaging member 20 to be moved downwardly away from the bight portion 12 into engagement with the file F to cause the latter to be urged into wedged relation within the pair of apertures in which it is seated. The file engaging mem- 26 are of the conventional coil type.

ber 20 will also be wedged into fixed relation between the file and the web 12 and this file-engaging member may be released from its wedging relation with respect to the file by merely rotating the screw element 21 in opposite direction to cause the end having the threaded bore 20a to move towards the web or bight portion 12.

My saw apparatus also includes means for positioning the file holder 11 adjacent the saw blade withthe file carried thereby being disposed in correct position in respect to the depth of the saw teeth. To this end I have provided a pair of yieldable positioning members 22 positioned in opposite ends of the elongate file holder 11 and projecting laterally from one side thereof. The file holder 11 is provided with an opening 23 at each end and the leg 14 in the positioning member 22 has one end thereof positioned within this opening, the other end portion thereof projecting laterally outwardly there from. These positioning members 22 are preferably formed of stainless steel since softer material would be subject to wear when positioned against the points of the teeth. These positioning members are adjustably and yieldably mounted on the file holder and the file holder is provided with a pair of elongate screws 24, each having an enlarged head 25, these screws extending through openings formed in the ends of the bight portion 12 as best seen in FIGS. 2 and 3. Each of these screws which is provided with a threaded shank also extends through an opening in its associated positioning member 22 and is threadedly engaged at its lower end by nut 25. Since the positioning members 22 are free to move vertically of the screw shank, a resilient means 26 are provided for normally urging the positioning member downwardly against the nut 25 and these springs Actually the positioning members 22 will engage the upper points or surfaces of the teeth to properly position the file in the recess defined by adjacent teeth of the saw, as best seen in FIG. 2. In order to adjust the apparatus for sharpening saws which may vary in the size and depth with regard to the saw teeth, the positioning members may be vertically adjusted by rotation of the screw to cause the nut to be moved upwardly which in turn causes the positioning member to be moved upwardly towards the bight portion 12.

In use, my apparatus may be used for quickly and accurately sharpening the teeth of saws. If a conventional cross cut saw S is to be filed, a file F will be positioned within the apertures 15 as illustrated in full line configuration in FIG. 1, to permit the cutting edge of every other tooth having this particular angulated bevel to be sharpened or filed. It should be pointed out however that prior to filing or sharpening either of the beveled surfaces of the teeth, the teeth should be filed down or jointed whereby all the teeth have the same height. When the tops or points of the teeth are filed down so that the teeth have the same height, these teeth will have a fiat reflective surface. When the file is positioned in the apertures 15 the side of the file positioned against the side 1511 which defines the aperture 15 will be positioned against the leading or cutting edge of the cross cut teeth while the side of the file which is positioned against the side 1512 will be disposed in engagement with the trailing edge of the next adjacent tooth. The file will be positioned at one end thereof extending between and engaged within the apertures 15 and projecting outwardly from the side of the file holder 11 as best seen in FIG. 1. The positioning members 22 will be positioned against the serrated teeth of the saw as best seen in FIG. 2 and the saw filing apparatus will then be moved from full line position in FIG. 1 to the dotted line position in FIG. 1. This initial positioning of the file with respect to the angle defined by the notch between the adjacent teeth plus the proper angulation with respect to the beveled cutting surface is extremely imconnection the user will be looking directly downwardly upon the teeth. During the initial step of the filing op eration the dull or unsharpened apex of the teeth will reflect light. This reflective surface will be somewhat reduced by the initial filing action as when the file is positioned within the pair of apertures. During the second step, the operator merely watches the reflective surface until the reflective surface disappears and then the operator will know that a point has been reached for that particular tooth. The next tooth Will be filed until the reflective surface disappears and in this manner all of the teeth will be sharpened and also will be of substantially the same height to insure effective cutting by the saw. In order to avoid unnecessary glare l have pro vided a glare shield 27, formed of a transparent but tinted material such as Plexiglas or glass which is secured to the bight portion 12 of the file holder 11 by means of the screws 24, the heads 25 of which clamp the glare shield 28 against the web portion.

It will therefore be seen from the preceding paragraphs that I have provided a filing saw apparatus which, while being of simple but inexpensive construction, permits a conventional hand saw of the cross cut or rip type to be readily and accurately filed. It will also be seen from the foregoing description that my novel saw filing apparatus is so arranged and constructed that a person unskilled in the operation of filing saws may readily and accurately file a saw. It will therefore be seen from the above description that I have provided a novel saw filing apparatus which permits saws to be filed in a more efficient manner than any heretofore comparable structures.

What I claim is:

1. A saw filing apparatus for use in filing saws comprising an elongate channel-shaped file holder including a bight portion having a pair of spaced apart legs depending therefrom, a plurality of longitudinally spaced, triangular-shaped apertures formed in each of said legs and being arranged in sets of opposed pairs, the apertures of each pair being of substantially identical shape and size and being slightly longitudinally offset with respect to each other to permit an elongate file of triangular cross-sectional shape to be positioned within a pair of said apertures with the longitudinal axis of the file being disposed in angulated relation with respect to the longitudinal axis of the elongate channel-shaped file holder, the apertures of one pair in one of said sets being longitudinally offset oppositely of the other pair of apertures in said one set whereby a file may be selectively positioned within each pair of apertures of each set for accurately sharpening oppositely angled teeth of a saw, releasable retaining means cooperating with said apertures for retaining a file in snug-fitting relation within a pair of said apertures, and a pair of yieldable positioning members positioned at opposite ends of said elongate file holder and extending laterally from one leg thereof for engaging the uppermost surfaces of the saw teeth of a saw and cooperating with said apertures for correctly positioning a file carried by said file holder in proper angulated relation with respect to the saw teeth.

2. The structure as defined in claim 1 wherein said positioning members are vertically adjustable relative to said one leg. 7

3. The structure as defined in claim 1 wherein the apertures of one pair in said one set are oppositely oriented with respect to the apertures of the other pair in said one set.

4. A saw filing apparatus for use in filing saws com-- prising an elongate, substantially U-shapcd file holder including a substantially flat bight portion having a pair of legs depending therefrom, a plurality of longitudinally spaced, triangular-shaped apertures formed in each of said legs and being arranged in sets of opposed pairs, each of said apertures being of substantially the same size and shape, the apertures of each pair being similarly oriented but longitudinally oifset with respect to each other, the apertures of one pair in one of said sets being longitudinally offset oppositely of the other pair of apertures in said one set whereby a file may be selectively positioned within each pair of apertures of each set for accurately sharpening oppositely angled teeth of a saw, an elongate retaining member cooperating with said apertures for releasably wedging a file downwardly in snug-fitting relation within a pair of said apertures, and a pair of yieldable positioning members carried by opposite ends of said file holder and extending laterally from one leg thereof for engaging the uppermost surfaces of the sawteeth of a saw and cooperating with said apertures for correctly positioning a file carried by said file holder in proper angulated relation with respect to the saw teeth.

5. The structure as defined in claim 4 wherein said retaining member is interposed between the legs of said file holder and in angulated relation with said bight portion when said retaining member is in wedging relation with a file.

6. The structure as defined in claim 5 wherein the apertures of each pair are similarly oriented with respect to each other and oriented difierently with respect to the apertures of other of said pairs.

7. The structure as defined in claim 4 and a substantially transparent glare shield member secured to the bight portion of said file holder and extending laterally from one side thereof for facilitating inspection of the teeth of the saw.

8. A saw filing apparatus for use in filing saws comprising an elongate substantially U-shaped file holder including a bight portion having a pair of legs depending therefrom, a plurality of longitudinally spaced triangular-shaped apertures formed in each of said legs and being arranged in said sets of opposed pairs, said apertures being of substantially the same size and shape and the apertures of each pair being similarly oriented but longitudinally offset with respect to each other, the apertures of one pair in one of said sets being longitudinally ofiset oppositely of the other pair of apertures in said one set, an elongate file of substantially triangular cross sectional configuration positioned in a pair of said apertures and projecting laterally from one leg of said file holder in angulated relation therewith, an elongate reraining member disposed between said leg and in inclined relation with bight portion and said file for wedging the latter downwardly in snug fitting relation within said last mentioned pair of apertures, means for releasably retaining said retaining member in wedging relation with the file, and a pair of yieldable positioning members carried by opposite ends of said file holder extending laterally from one leg thereof for engaging the uppermost surfaces of the saw teeth and cooperating with said apertures for correctly positioning said file in proper angulated relation with respect to the sawteeth of a file when said apparatus is used for filing such a saw.