US2552164A

US2552164A - File sharpener

Info

Publication number: US2552164A
Application number: US85685A
Authority: US
Inventors: Freeman C Foss
Original assignee: Individual
Current assignee: Individual
Priority date: 1949-04-05
Filing date: 1949-04-05
Publication date: 1951-05-08
Anticipated expiration: 1968-05-08

Description

May 8, 1951 F. c. Foss 2,552,164

Filed April 5, 1949 4 Sheets-Sheet l May 8,'1951 F. c. Foss 2,552,164

FILE SHARPENER Filed April 5, 1949 4 sheets-sheet 2 f MJ 1////////////f Freeman C. `/-'0ss INVENToR.

BY @MMM ana/Wawy mm May s, 1951 F. C. FOSS 2,552,164

FILE SHARPENER Filed April 5, 1949 4 Sheets-Sheet 3 691.. ,fmn :I r

' f Freeman C. Foss JNVENTOR. BY @Maa/2@ fl WWW" A F. C. FOSS FILE SHARPENER May 8, 1951 4 Sheets-Sheet 4 Filed April 5, 1949 Freeman C. Foss INVENTOR.

Patented May 8, 1951 UNITED STATES PATENT OFFICE FILE SHARPENER Freeman C. Foss, Twin Falls, Idaho Application April 5, 1949, Serial No. 85,685

2 Claims. 1 This invention relates to a le Sharpener. An object of this invention is to sharpen a le by the technique of holding the le to be sharpened in a pair of relatively movable jaws and moving a grinder in an arcuate path so that the teeth of the le may be sharpened, and ad-v vancing the le after one tooth is sharpened by means of moving the file in an arc, a foot carried by the support for the Sharpener being in engagement with a tooth of the file, urging the file forward with respect to the file holder and then, while the file is moved back through the same arc but in the reverse direction the foot slipping over the said tooth to the region between the next adjacent teeth in order to render the device ready for a second sharpening operation.

Another object of this invention is to provide a mechanism for supporting the above functions which is capable of various adjustments desirable and necessary for performing an effective and substantially exact job on the le.

An ancillary object is to utilize a single handle for releasing the jaws in order that the le may be advanced and also for swinging the jaws as a unit about a pivot point also in order that the 4lile may be advanced. Y

Another purpose of this invention is to provide an inexpensive portable device which is within the purchasing power of fender and body shops as well as small machine shops thereby avoiding the necessity of sending les to a regular establishment for and specializing in such procedure.

Other objects and features of the invention will become apparent in following the description of the preferred form of the invention, illustrated in the accompanying drawings, wherein:

Figure 1 is a perspective view of the preferred form of the invention, showing one operative position thereof;

Figure 2 is a perspective view of the device shown in Figure l showing another operative ccndition of operation;

Figure 3 is a plan view of the device shown in Figures i and 2;

Figure 4 is a side view of the device shown in Figure 3;

Figure 5 is an enlarged fragmentary perspective view illustrated particularly of the means for advancing the file which is shown in part;

Figure 6 is a sectional View taken substantially on the line 6 5 of Figure 4 and in the direction of the arrows;

Figure 7 is a sectional view taken substantially. on the line lwl of Figure 4 and in the direction of the arrows;

Figure 8 is a plan View of the clamp which includes a pair of jaws; and

Figure 9 is a perspective view of a support for the grinder holder and grinder.

It is present practice for body and fender metal workers to simply replace their files when they have become worn or send them to a shop to have them sharpened. As a practical matter files are almost always used far too long a time because of the trouble and expense of sending them out to shops for sharpening purposes. It has been found that a shop of average size requires from l5 to 50 files in order that they could alternately'v send them out and have them sharpened yet have a sufficient supply for the daily needs. As a further practical consideration a mechanic often receives not his own files from the repair shop but other files, the les being confused.

In recent years due to the development of electric motors which have attained speeds of 20 thousand revolutions per minute many developments have been made taking advantage of such motors. Previously it was substantially impossible to operate a grinder from a direct drive from a motor at sufciently high speed in order to sharpen the hardened steel cutting edges of the teeth of the le with any degree of success. The present invention utilizes one of such motors.

The present invention fullls a definite need in the trade and it is a handy, easily usable and accurate device for sharpening files either wholly or in part, as when only a small portion of the file becomes damaged or dull.

For illustrative purposes and in order to provide an environment for the invention, a vise lll is indicated as holding a block l2 which may be of wood, metal or any other material. The vise is used in its conventional capacity that is, in

upstanding ange i8 xed to one marginal edge'- thereof. v The ange i8 is adapted to engage the le 20 along the edge thereof in clamping contact. The files to be sharpened in conjunction with the present invention are of course, conventional in character.

The other jaw is composed of a stout rod. One

portion of the rod is substantially U-shaped (Figure 2) consisting of a web portion 22 and

upstanding legs

24 and 26 respectively which are integral therewith. A rod or handle portion 28 extends from one end of the said web portions 22 and is slidable in a bearing or boss 86, xed to the relatively stationary jaw.

Ears 32 are provided on the flat plate I6 and eX- tend from the marginal edge opposite the fiange I8. The ears form guides for the

upstanding legs

24 and 26 in movement of the jaws with respect to each other. They also act as a steadying means when 'fthe le 2.8 is being clamped.

Means mounting both of said jaws for pivotal movement as a unit is provided. This means consists of a pivot pin 36 extending through the at plate I6 and terminating in a bearing 88 which is formed as an integral portion of a support generally indicated at 4D. (Figure 9.)

The said support is fixed to the lblock |-2 .by means of screws or bolts 42 passing through suitable openings 44 which are in a flange 46 kof the support 40. Hence, by movement of the rod, this clamp I 4 ma?,7 be .swung in an arc thereby moving the file 20. Further, the same rod 28 maybe slid inwardly 'of the said clamp thereby releasing the movable jaw from engagement with the file 26. To insure Va steady `and .firm grip on the file 28 the legs 24, y26 respectively may have .flats (unnumbered) on one :side of each vwhich are -cooperative with oneof the ears 32 in each group forming an -overlap connection as is seen in Figure 3.

Referring vagain to the support 46, it is apparent from inspection of Figure 9 that -there is a U-shaped portion generally indicated at 4l in its makeup, the bottom leg 48 thereof resting on the block I2 and the top leg thereof 58 being disposed above the clamp and above the le 2D supported by the said clamp. A pair of apertures 52 for selective accommodation of a pivot pin 4isprovidedin the upper leg 56. This -pivot vpin accommodates the 'spaced bearings '56 and 58 respectively for pivotal movement. One or both of the said bearings may be of the split 'clamp type and may have a set screw 6|] therein for clamping.

A gri-nder holder generally indicated at 62 has as an integral portion thereof the said

bearings

56 and 58 respectively and is mounted for pivotal movement on the said pin 54. A spring or other suitable resilient biasing means 64 is anchored to a lug 66 4and to one of the bearings for constantly returning the said holder 62 to one position. The spring 64 constantly biases the holder to the desired position for operation. A stop which consists of a block 68 welded to the upper leg 50 and having a set screw 18 therein engaging the bearing 58 is provided in 'order to limit the travel of the grinder holder which is by the above described structure mounted for pivotal or arcuate movement.

A small high speed motor "I4 is carried by the holder and has a grinding wheel or disc or other suitable abrading means 'i6 carried by the chucks I8 which are mounted on the drive shaft of the motor 14. As the holder 62 is swung arcuately the grinder or abrading member does the actual sharpening of the teeth of the le 28.

In operation thus far described, the structure maybe actuated as shown in phantom in Figure 3. The rod or handle 28 may be swung arcuately thereby pivotally moving the clamp as a unit. Also, the holder 62 may be swung arcuately about the pivot pin 56 as an 'axis in order to move the abrading means over the file.

In order to release the jaws from clamping engagement with the vle the handle or rod 28 is slid inwardly of the bearings 30 against the compressive force of the spring which reacts on an adjustable collar 82 mounted on the rod 28 and also on the bearing 38. A return spring 84 is attached to a post 86 and in a suitable aperture (unnumbered) in the bearings 30. Hence, since the support 68 is stationary and the clamp I4 movable, the spring 84 is stretched upon arcuate movement thereby returning the clamp in the pivotal manner when the handle 28 is released for carrying out the function of the device.

Another function of the post 86 is realityl an adjustable screw having a lock nut 88 thereon,

tis to .set the device for ne or coarse teeth files.

This is accomplished by the end of the screw 86 contacting vthe '1i-lange I8 (Figures 3 and 5) thereby limiting the return of the clamp and also setting the clamp.

A screw 90 is disposed in the bearing 3U extending therethrough and engaging the flange 46 of the vsaid support 46. This screw is also utilized yfor the purpose of setting the device with relation to the grinder disc 'I6 by limiting the pivotal travel of both of the jaws when they travel as a unit.

Referring to the -holder 62 which includes the

bearings

56, 58 as discussed, an arm 92 is the specific carrier -for the bearings and has a guard 94 either xed thereto or provided integral therewith. This guard is for the said grinder T6.

A lhandle 96 is secured to the arm 92 for vpivotally operating the holder 62.

A plate 98 is fixed to the arm 92 for pivotal movement -by means of a screw |06 having a resilient bushing |82 associated therewith. Hence, by loosening the said screw |00 the plate 98 which carries the motor 14 may be pivoted thereby adjusting the angle of inclination of the grinder 'I6 with respect to the teeth of the le 28. A set screw I 64 is carried in a suitable bearing |06 mounted-on the said plate 98 and is in operative engagement with a platform |68 xed to the arm 92.

Means for advancing the le the distance equal to the space between teeth is provided and has been partially described. The remaining structure consists of a foot generally indicated atl I including a plate I I2 which is mounted on the arm 82 (Figure 5). A chisel-like member I I4 which may also be termed a foot has a right an'gularly extending flange I I6 at one end thereof and a rather sharp point on the other end thereo'f. The ange has a set screw I I8 carried thereby and a lock nut |26 for the set screw. This set screw bears on a post I 22 which is carried by the plate ||2 in order to somewhat limit the movement of the floatingly supported foot ||4. A spring or other resilient biasing means |24 is carried by another post |26 also mounted on the plate I2 and in a suitable unnumbered aperture in the right angularly extending flange I I6. This spring constantly pulls the foot downwardly. In order to further limit the floating movement of the said foot |I4 a substantially L-shaped guide |28 is carried by the said plate I I2 and has a set screw |35 therein bearing against a side of the said foot. Hence, the foot is limited in its travel by means of a guide |28, the post |26 and the set screw |I8.

The end of the foot is in engagement with the teeth of the le 26 which is to be sharpened.

In operation teeth are sharpened for various iiles as follows:

The device is retained in a suitable support such as the vise l0. It is retained as described elsewhere in the specification.

The le 20 which may be of any suitable type is retained between the jaws by simply sliding the dual purpose handle 28 against the biasing force of the spring 80 and depositing the le between the jaws. By releasing the handle the jaws automatically clamp the file in place.

With the left hand the grinding assembly is lifted and the le is pushed under the foot until the end thereof catches the rst full tooth of the le and the file is pulled back against the foot until it is tightened with respect to the foot. The foot is checked to see how it tracks in this tooth by sweeping the grinder assembly back and forth and appropriate adjustment is made by means of the screw 90 so that it tracks smoothly. The screw 8S is used to compensate for variations due to different manufacturers make files. The foot should not in its arc leave the back of the tooth nor should it crowd so that it moves the le slightly in swinging the holder 62 about the pivot pin 54.

I'hen by slight adjustment of the screw |04 (and of course the screw |00 being loosened for this purpose) the pitch of the abrading member is adjusted to the pitch of the tooth. The abrading member should now be fairly close to the proper position and by moving the stone spindle in or out it is ehucked tightly so that it will miss the immediately preceding tooth by about :Je of an inch.

The motor is energized and by slowly tightening the stone set screw while sweepingthe holder 62 in its arcuate travel the stone or abrading member 14 is brought into contact on the tooth but the motor is not pulled downward. For touch up jobs one or two sweeps should be all that is necessary. Four may be made but all of the teeth should be given the same or substantially the same grinding. Experience is of course necessary in order to arrive at the most satisfactory operation.

In order to advance the le the handle 28 is moved in order to swing the clamp I4 about the pin 36 as an axis. This moves the clamp in an arc and one complete cycle of movement includes a swinging movement in one direction and an equal swinging movement in the return direction as influenced by the spring 84. The handle 96 is held stationary while this movement is taking place; the foot will slide the file forward since it is retained at a position stationary and spaced from the pivot axis of the clamp.

In returning the handle 28 either manually or manually assisted by the spring 84, the foot will slip over one tooth due to its floatingly supported nature and be in position in the next tooth.

In the swinging movement it is only necessary to slide the handle 28 inwardly in order to release the jaws in order that the sliding movement of the le 20 may be accomplished in a smooth manner.

It is apparent that variations may be made without departing from the spirit of the invention.

Having described the claimed as new is:

1. A sharpening device for a le comprising a ille clamp having relatively movable jaws, a relatively stationary grinder support, means mounting said le clamp on said support for pivotal movement, a rod nxed to one of said jaws and movably carried by the other jaw for moving one of said jaws with respect to the other jaw, a spring reacting on said jaws constantly urging said jaws toward each other to clamp a le therebetween, a grinder holder mounted for pivotal movement on said support, a grinder carried by said holder, a foot movably mounted on said holder for engagement between teeth of a le in said clamp, the le clamp being pivotally movable about a vertical axis while said foot is held stationary and located at a point spaced from said axis whereby said foot will override one tooth of the le and come to rest between the next adjacent teeth to slide the le in the clamp an amount equal to the width of a tooth, a spring reacting on said le clamp and said stationary grinder support to pivotally return said clamp, and means carried by said clamp and engaging said support to shift said le clamp pivotally a selected amount to center the grinder with respect to the file in the le clamp.

2. A device for sharpening a le comprising a le clamp which is composed of a relatively stationary jaw and a movable jaw, a support, means mounting both of said jaws on said support for pivotal movement as a unit, a holder, a grinder, means mounting said grinder on said holder, and a pivotal connection fixing said holder to said support for movement about a vertical axis whereby said grinder may be swung arcuately to grind a le retained between said jaws. means supported by one of said jaws and attached to the other jaw for moving said jaws relative to each other and for swinging both of said jaws as a unit about a vertical axis, a foot carried by said holder and spaced from the last-mentioned axis, said foot being engageable between the teeth of the file to advance the le when said jaws are pivotally swung as a unit in an arc for substantially one half a pivotal cycle, said foot being mounted for restricted movement on said holder so that the foot will override one tooth when the jaws are moved as aunit upon completing one half of the pivotal cycle.

invention, what is FREEMAN C. FOSS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,777,135 Bailey Sept. 30, 1930 2,212,999 Faulder Aug. 27, 1940 2,222,034 Jackson Nov. 19, 1940 2,375,703 Swartzwelder May 8, 1945