US2951400A - Arrowhead sharpener - Google Patents

Description

ARROWHEAD SHARPENER George D. Renne, Jr., 6925 Colbath St., Van Nuys, and

Edward C. Jordan, 6254 Beeman Ave., North Hollywood, Calif.

Filed June 2, .1958, Ser. No. 739,423 7 Claims. (Cl. 76-86) This invention relates to blade sharpening devices and more particularly to an improved hand-held sharpener for Sharpening knife blades generally and more especially the blades of arrowheads.

There has been an unsatisfied need for a simple, inexpensive and more effective device for sharpening cutting blades generally and of bladed arrow tips in particular to the end that the same may be reconditioned and sharpened speedily, with precision and without hazard to the person. Resort has heretofore been had to numerous expedients to accomplish this purpose but these are subject to numerous shortcomings and disadvantages Which it is the object of the present invention to obviate. For example, prior devices have been awkward to use, have presented serious hazards to the user, and have been particularly inadequate and unsatisfactory for sharpening arrowheads having more than two radially disposed blades converging at the pointed end of the head.

By the present invention there is provided a very compact, simple sharpener adapted to be held between the thumb and fingers near the forward end of its handle and with the other handle end seated in the palm of the hand leaving the sharpening blades projecting scissors-fashion from the forward end of the sharpener. The design is such that the juxtaposed facing corners of the sharpener blades are normally barely in overlapping relation at their outer ends and in readiness to receive the blade edge to be sharpened as it is drawn across these corners. Simple spring means concealed within the implement maintains a suitable pressure on the blades essential to the sharpening operation. A feature of the invention resides in the fact that the blades are reversible endwise as well as about their longitudinal aXes to the end that all four corners at each end of both blades may be brought into sharpening position sequentially as a given set of cutting corners becomes drilled in use. Accordingly, it may be said that the sharpening implement has four lives since its full cutting and sharpening efliciency may be restored this number of times merely by changing the relative positions of the cutting corners used in sharpening.

Accordingly, it is a primary object of the present invention to provide an improved sharpening device useful in sharpening blades of all kinds, and arrowheads in particular.

Another object of the invention is the provision of the blade sharpening implement having a pair of springpressed blades pivoted scissors-fashion within a handle with the outer diverging ends only thereof exposed beyond the end of the handle.

Still another object of the invention is the provision of a hand-held blade sharpening device employing a pair of blades pivoted scissors-fashion and wherein each corner at both ends of the blades can be rotated and reversed until each corner of both blades has been employed for sharpening purposes.

Another object of the invention is the provision of 2 a blade sharpening implement utilizing a pair of spring pressed blades adapted to sharpen blades to provide either a tapering cutting edge or one having hollow faces.

These and other more specific objects will appear upon reading the following specification and claims and upon considering in connection therewith the attached drawing to which they relate.

Referring now to the drawing in which a preferred embodiment of the invention is illustrated:

Figure 1 is a view in perspective showing the sharpening implement of the present invention in cutting relation to the edge of an arrowhead undergoing sharpening;

Figure 2 is a longitudinal cross-sectional view through the handle portion only of the implement taken along line 22 of Figure 1;

Figure 3 is a plan view taken along line 33 on Figure 2 and showing the position of the parts with one handle half removed;

Figure 4 is a fragmentary perspective View similar to Figure 1 but showing the sharpening implement in use to sharpen a three-bladed arrowhead;

Figure 5 is a view similar to Figure 4 but showing the sharpener as it approaches the tip end of a three-bladed arrowhead.

Figure 6 is an enlarged fragmentary view of the ends of the sharpener blades positioned to sharpen a hollowedged blade; and

Figure 7 is an enlarged fragmentary view similar to Figure 6 but showing the sharpener blades positioned to sharpen a blade with a V-shaped edge.

Referring now to the drawings and more particularly to Figures 1, 2 and 3, there is shown a sharpening implement 10 incorporating the present invention and having a handle formed in two halves 11, 12. Preferably these handle halves are formed in the manner shown to the end that the converging lateral sides 13, 13 at the forward end of the handle may be gripped between the thumb and the forefinger with the bulbous rear end 14 seated in the palm of the hand thereby facilitating the accurate and fully controlled manipulation of the implement in use.

Referring to Figures 2 and 3 it will be observed that the larger forward end of the handle is provided interiorly thereof with a generally circular chamber 15 having a Venturi-shaped passage 16 opening therefrom through the forward end of the handle. Protruding across chamber 15 generally centrally thereof is a'generally triangular shaped boss 18 having its pointed end in alignment with passage 16 and its rear end 19 spaced from the side wall of chamber 15 'at a point opposite passage 16. Boss 18 may be, and desirably is, formed integral with one of the handle halves and has a height corresponding to that of chamber 15.

The sharpening blades comprise a pair of identical elongated blades 21, 22 of any suitable blade sharpening material such as specially tempered steel or the like effective in shaving the edges of cutting blades. Blades 21 and 22 are preferably rectangular in cross-section and are provided with openings 23 offset to either side of their longitudinal midpoints to receive a pivot pin 25 such as a small bolt having a slotted head 26 at one end and a nut 27 threaded to its opposite end. It will be understood that pivot pin 25 is eifective in holding blades 21 and 22 pivotally supported scissors-fashion within passage 16 and in holding the two halves 11 and 12 of the handle assembled. A similar screw or bolt 27' is provided at the opposite end of the handle to hold the rear end 14 of the handle halves together.

The remaining structural feature of the sharpening im- 7 plement comprises a stiff arcuate spring 30, this spring fitting loosely within chamber 15 with its opposite ends bearing firmly against the outer lateral edges of blades 21, 22 thereby urging these toward one another against the opposite sides of boss 18 in the manner shown in Figure 3. In this normal position of the blades, the adjacent lateral edges at the exposed ends are slightly open, as is indicated at 31 in Figure 3. It is also pointed out that the blades ends are rounded in such manner as to cooperate with one another to sharpen blade edges with hollow or concave opposed faces immediately rearward of the cutting edge. These rounded endsalso serve as a pilot to guide the edge being sharpened between blades 21, 22 in order that the blade being sharpened may be provided with a conventional tapered edge. In fact, in normal usage it is customary to first sharpen the blade with a tapering edge utilizing the facing lateral corners of blades 21, 22 following which the outer rounded ends 32 of the blades are used to provide a hollow face in each of the tapering faces.

In use, the described sharpening implement is grasped in the right hand with the thumb and forefinger pressed against the opposite lateral side walls 13, 13 of the handle in the area opposite pivot pin 25, the bulbous end 14 being held seated in the palm of the hand by pressure of the little finger and the third finger. The blade to be sharpened, such as arrowhead 35 and its attached shaft 36, is grasped in the left hand with the edge 38 to be sharpened seated in V-notch 31. While so positioned, shaft 36 is preferably held steady as the sharpening instrument is moved along the edge being sharpened and from the heel of the blade toward its toe or pointed end. It will be recognized that one pair of the juxtaposed sharp corners forming the V-slot between the blades as the arrowhead is forced therebetween are thereby drawn along the opposite faces of the cutting edge to shave material therefrom under resilient pressure constantly maintained on blades 21, 22 by stiff spring 39. The edge 38 may be drawn between the sharpening blades one or more times as necessary to achieve the desired cutting edge on the arrowhead following which the shaft is rotated 180 degrees about its axis so that the cutting edge on its opposite side may be similarly sharpened. If a hollow edge is desired, the user applies insufficient pressure to open blades'21, 22 and proceeds to draw the edge of the arrowhead across and between the rounded ends 32 only of blades 21, 22.

In sharpening an arrowhead 40 mounted on a shaft 41 and having three blades 42 spaced 120 degrees apart circumferentially of the shaft and converging to a point 43 at its forward end, the operator follows the same procedure described in connection with the two bladed arrowhead 35 in Figure 1. Usually it is preferred to apply the rear end of the cutting edge undergoing sharpening to the sharpening implement and hold the cutting edge stationary as the sharpening implement is advanced therealong in a direction away from the operator. This mode of use assures that the arrowhead will be sharpened for its full length without danger of leaving burrs or an unsharpened terminal end at its tip. Referring to Figure 5, it will be observed that the proximity of the two' blades to either side of the one undergoing sharpening does not interfere with the passage of blades 21 and 22 past the very tip of the arrowhead owing to the smallness of V-slot 31 at the outer end of the sharpening blades in their normal or substantially closed position.

After a period of use the adjacent corners at the outer ends of blades 21 and 22 may become dulled and ineffective to provide a desired cutting action. This is quickly and easily remedied by removing pivot bolt 25 and assembly screw 27 thereby permitting blades 21 and 22 to be rotated about their longitudinal axes to bring the exterior corners along the outer lateral edges of the blades into sharpening position, following which spring inbefore stated, it is to be understood that it is merely illusrative of the presently preferred embodiments of the invention and that no limitations are intended to the 'details of construction or design herein shown other than as defined in the appended claims.

We claim:

1. A blade sharpening device adapted to be held substantially confined within the palm of the hand as the device is drawn lengthwise along the edge of a blade being sharpened, said device comprising a smooth-surfaced contoured handle of a size conveniently nestable in the closed palm of the users hand in a manner leaving one end extending slightly beyond the hand, a pair of flattened sharpening blades projecting slightly from said one end of said handle and arranged scissorsfashion within about pivot means supported near one end of said handle and with their exposed outer ends diverging but with their adjacent edges substantially closed in overlapping relation, the adjacent lateral edges of said pair of blades being smooth, straight-edged and gradually diverging from one another and cooperating to shave the opposite faces of a blade edge simultaneously to sharpen the same as the blade edge is drawn lengthwise between the blades along a path generally perpendicular to the plane of the blades, spring means concealed within said handle and arranged to urge said diverging outer ends pivoted toward one another to maintain the juxtaposed lateral edges of said blades pressed firmly and resiliently against the opposite converging sides of a blade edge as the latter is drawn lengthwise between the outer ends of said sharpening blades, said spring means being effective to maintain a desired load on said blades irrespective of the tightness of the users grip on said handle.

2. A sharpening device as defined in claim 1 characterized in that said blades are reversible end-for-end in said handle whereby the same may be reversed to have their inner ends exposed relative to said handle to present fresh sharpening edges after their other ends have become dulled from use.

3. A sharpening device as defined in claim 1 characterized in that said blades are provided with two pairs of openings for receiving said supporting pivot, said pairs of pivot openings being offset to either side of the mid-length of said blades.

4. An arrowhead sharpening device comprising a handle adapted to be held in the users hand, said handle having a chamber therewithin opening through one end of the handle, a single pair of relatively thin sharpening blades of generally rectangular and generally uniform cross-section from end-to-end thereof and pivoted scissors-fashion between their opposite ends at a point near the open end of said handle, the adjacent sharpening edges of said sharpening blades being straight and smoothsurfaced, the outer diverging ends of said blades projecting beyond the handle end and their opposite ends being concealed within said handle chamber, a split ring spring embracing the inner ends of said blades from their outer lateral edges in-a manner urging their outer ends together, and stop means preventing said springs from closing said blades beyond a position in which their outer ends are positioned to receive the edge of an arrowhead therebetween.

5. A sharpening device as defined in claim 4 characterizcd in that the outer ends of said blades are rounded to provide a pilot guiding a cutting edge to be sharpened between said blades in a manner forcing the blades to open away from one another as pressure is brought to bear on said handle in a direction toward the cutting edge undergoing sharpening, said rounded ends having sharp edges shaped to cooperate with one another to sharpen a blade with hollow faces immediately rearwardly of the cutting edge proper.

6. A blade sharpening device having a pair of elongated hardened sharpening blades, means pivotally securing said blades together scissors-fashion between their opposite ends, means positioned between one end of said blades holding the opposite ends slightly open to provide a V-notch sufficient for the insertion of a cutting edge therebetween while undergoing sharpening, spring means connected across said one end of the blades urging the opposite ends toward one another, handle means removably secured about the spring supporting ends of said blades, and said blades being reversible end-to-end as well as rotatable about their longitudinal axes whereby each pair of lateral edge corners on both ends of said blades can be brought selectively into blade sharpening position until all corners have become dulled from use in sharpening blades.

7. A blade sharpening device adapted to sharpen blades selectively with either tapering or hollow faces at the users option, said device comprising a single pair of flat hardened blades pivoted together scissors-fashion intermediate the ends thereof, the lateral edges of said blades being smooth and sharp from end-to-end and effective to sharpen a knife blade as it is drawn thereacross, spring means urging one adjacent pair of ends closed toward one another, stop means permitting said pair of ends to barely close, said pair of ends being rounded toward one another in a manner such that the sharp edges of these rounded ends cooperate with one another to form hollow faces in the edge of a knife blade drawn thereacross, and said spring means permitting said blades to pivot away from one another to admit the edge of the knife as the knife blade is pressed firmly between said rounded ends whereby the opposed corners along the facing edges of said sharpening blades are efiective in providing a tapering edge on the knife blade as it is moved crosswise of said open sharpening blades.

References Cited in the file of this patent UNITED STATES PATENTS 558,407 Miller Apr. 14, 1896 772,542 Sullivan Oct. 18, 1904 1,041,631 Johnson Oct. 15, 1912 FOREIGN PATENTS 603,083 Germany Sept. 24, 1934

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