US2487992A - Knife sharpener - Google Patents

Description

Nv. 15, 1949 w. A. swlGART KNIFE SHARPENER Filed June l5, 1947 INVENTOR. mit/@MWA im' am bril/:dgl IF Pl.

a l y Patented Nov. 15,` 1949 UNITED` STATES PATlf'lllll'v KNIFE SHARPENER Walter A... Swigarti. Qhiceo, 1.11@ Application June. L3, 1947,..Serial No.. 754:2324.

' I (el. .i1-2.0.5)

4z Claims. 1

This invention relatesl to certain newand use` ful improvements in knife Sharpeners.

More particularly, the invention relates to asharpening device for sharpening the cutting edges of the bladesl of a paper cutter'and trimming machine. As such anl invention has for its principal object the provision of an improved construction of this character. it, will be highly enicient in use andA economical, in manufacture.

As the knives of a paper cutting and trimmingr apparatus usually are ofj substantial weight which makes it difficult to handle the. blade for sharpening purposes. I have devised a device. which.. may be. supported upon the blade with the sharpening elements at a proper inclination with. respect to. the beveled cutting edge portion oi the blade with ease and. with. thegreatestd'egree. of. eioienoy during the sharpening operation and the. minimum degree of danger to the operator` Another object Qt my invention resides in the manner of holding the sharpening elements within a holder and forlocatingl these elements properly with respect to the beveled cutting edge of the blade; f

Other objects will appear hereinafter.

The invention. consists in the navel combination and arrangement of parts. to be hereinafter described and claimed.

The. invention will be best understood; by reference to the accompanying drawings showing the preferred form of construction, and in which:

Fig. 1 is a perspective view of the invention in applied position upon a blade;

Fig. 2 is a sectional detail View taken substantially on line 2-2 of Fig. 3; and

Fig. 3 is a view of the blade engaging surface of my sharpening device.

The several objects of my invention are accomplished by the preferred form of construction shown in the accompanying drawings and in which a holder is indicated at I0. This holder includes a back plate I I from which extend integral side anges I2 and intermediate flanges I3. The flanges I2 together with the flanges I3 provide with the back plate II separate channels I4 within which are adapted to be positioned the sharpening elements I5. These sharpening elements I5 may be formed of any approved material and are preferably whetstones.

The 4sharpening elements are yieldably held within the channels I4 by means of suitable spring leaves I6 disposed between the sharpening elements and the flanges I3 and of a sufficient resiliency to yieldably urge the sharpening elements I5 against the anges I2.

o the holder I-Il between the flanges I3.

These sharpening elements arereleasably latched' in the channels I4 by means of a retainer plate I1 having extending therefrom a binding screw I8 projecting through a slot I9 formed-in Onthis binderI screw is a latch nut 20 serving to latch the retainer plate Il in an adjustable position with respect to the sharpening elements- I-5.

This retainer plate has an edge portion 2-I provided with a substantially nat outer surface 2'2l which is adapted to engage the fiat surface 23'of the knife blade 24 beingsharpenedA A guiding head is indicated at 25v and comprises a body'portion 2.6 positioned in a slot 2T formed in the back plate I'I between. the. upper end portions o f the flanges I3. Secured to this` body 26 as at 28 is a plate 29 carrying an adjustable screw 30. This guiding head 25 is pivotally connected by a pintle. pin 3l tothe 'anees l3.. The guiding head Z5. includesa. socket 32. in which is. adapted to be mounted a guide block 33 0.1: a whetstone (notshownh the. latter being of the same size. and shape. asv the guide vblock 33 whereby it may be substituted for the; block 3.3. for reasons. hereinafter set forth. l

This block. 33. is clamped within the socket 32 by means. of. a face plate 32 secured to the guiding head 25 by means of screw bolts 34...

Thev guide. block 33 has. a. portion thereof. re moved to. provide an open area 35. whereby when: the Sharpener is mounted upon the blade 24 the tip edge 36 of the cutting edge portion of the blade will be disposed at some point Within the area 35 free from contact with the block 33.

To complete the invention there may be engraved, stamped, or impressed upon the plate II a scale 3B', the lines of which may be numbered as at 31 and these lines may be spaced a predetermined distance aparat so as to locate the flat surface 22 in close position with respect to the point of merger between the at surface 23 and the beveled edge portion 23' of the blade 24, it being pointed out that this bevel 23 varies in different types of cutter blades.

In use after the retainer plate I'I has been properly adjusted for proper engagement with the flat surface 23 of the blade 24, the holder is mounted upon the blade 24 with the guide block 33 engaging the blade 24 in the manner shown in Fig. 2 and with the whetstones I5 iiatly engaging the beveled edge 23'. By grasping the holder I0 between the iingers and the thumb the sharpener may be readily and conveniently reciprocated over the cutting edge portion of the blade 2-4 until a proper cutting edge has been restored 3 to the blade 24. Should the whetstones become Worn they may be removed from their seated positions in the channels I4 and reversed or replaced by new whetstones.

After the sharpening operation has taken place there will be found to exist upon the cutting edge 36 minute burrs which should be removed. This is accomplished by removing the guide block 33 and replacing the same with a whetstone or the like andY then reciprocating the Yholder relative to the blade until the burrs Ahave been removed.

It will be apparent that my improved knife Sharpener can be operated with the minimum degree of effort on the part of the operator with the minimum degree of possible injury to the operator, the latter resulting from the fact that the sharpening device by virtue of its guiding head positioned upon the blade cannot be readily displaced by accident or otherwise during the sharpening operation.

The sharpening elements are arranged in the holder in a manner such as to permit ready removal thereof for repair or replacement.

I-t will be also apparent that the retainer plate l1 in its function to properly position the sharpening elements with respect to the beveled portion 23 of the blade 24 serves to properly guide these sharpening elements at a proper inclination with respect to the blade 24 whereby an accurate beveled cutting edge will be maintained.

While I have illustrated and described the preferred form of construction for carrying my invention into effect, this is capable of variation and modification without departing from the spirit of the invention. I, therefore, do not wish to be limited to the precise details of construction set forth, but desire to avail myself of such variations and modications as come within the scope of the appended claims.

Having thus described my invention, what I claim as new and desire to protect by Letters Patent is:

1. A knife Sharpener comprising a holder, sharpening elements carried by the holder, means for removably mounting the sharpening `elements within the holder and including an element adapted to engage the at side of aknife blade for positioning the sharpening elements upon the beveled edge portion of the cutting edge of said knife blade, and a guide head pivotally carried bythe holder and having means adapted to engage the fiat surface of the blade opposite the beveled edge of the knife.

2. A knife Sharpener comprising a holder, sharpening elements carried by the holder, means for removably mounting the sharpening elements within the holder and for positioning the sharpening elements upon the beveled edge portion of the cutting edge of a knife blade, a guide head pivot-,ally carried by the holder and having means adapted to engage the flat surface of the blade opposite the beveled edge of the knife, and means for adjusting said guide head relative to said blade.

.3. A knife sharpener comprising a holder, sharpening elements carried by the holder, means for removably mounting the sharpening elements Within the holder and for positioning the sharpening elements upon the beveled edge portion of the cutting edge of a knife blade, a guide head pivotally carried by the'holder and having means adapted to engage the ilat surface of the blade opposite the beveled edge of the knife, said retainer plate having means for adjustment relative Ito said sharpening elements, and means for adjusting said guide head relative to said blade.

4. A knife Sharpener comprising a holder providing a channel, a guide block pivotally carried by said holder, a sharpening element mounted in said channel, a wall of said holder providing an elongated slot, a retainer bar extending transversely of the element, a screw extending through the slot and bearing upon said wall and having connection with the bar to draw the bar into clamping engagement with the element to clamp said element in said channel, said bar and said guide block having portions engaging a knife on opposite sides thereof with the element bearing upon an edge of the knife to be sharpened to guide movement of the holder relative to said knife edge.

WALTER A. SWIGART.

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

UNITED STATES PATENTS

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