US2732620A - gibbs - Google Patents

Description

Jan. 31, 1956 R. J. GIBBS 2,732,620

MULTIPLE BLADED ROOFQIG AND PRUNING KNIVES Filed .1511. 18, 1952 JNVENTOR. R0) J. 6/535 A T TOR/V5 Y United States Patent A,

b73162! MULTIPLE BLADED nooFrNg; rnurgnsg Roy J. Gibbs, Sanlliggp, ,Qglif. pp icatihn Ja u ry 8, 1952,, Ser al Ng- 2 1, 3 Claims. (cl. sofiaao My invention relates to multiple :bladed cutting knives, particularly as adapted for the cut-ting and laying of asphalt roofing material and also for pruning purposes; and its objects are, to provide a multiple bladed knife of novel construction capable of cutting o gh and fractory material with minimum physical exertion and prevention of fatigue on the part of the workman; to dispense with the single bladed knife ordinarily used by roofers and pruners, and to substitute therefor a tool with an adjustable, replaceable adjustable attach ment having a plurality of blades, usable separately and successively for cutting purposes; to allow said attachment readily to be turned and readjusted for presentation of a single blade, and also to be removed and replaced for renewal or resharpening upon the blades thereof becoming worn or dull; to render the blades of said attachment available for cutting purposes when the handle of the knife is in either horizontal or upright position; to render it feasible to employ thinner blades for the cutting of asphalt roofing material than has heretofore been deemed practicable in the art; to render the parts readily accessible for inspection, adjustment, renewal, replacement and repair, and in general to provide a device of this character which is economical of construction, saving of labor, eflicient in action and of prolonged life and durability. These and other objects will appear from the drawing and as more specifically hereinafter set forth.

My invention more particularly consists in a triangular, square or other polygonal shaped metallic disc, the sides of which are sharpened to form cutting edges or blades, preferably made curved or concave in form; the said disc being thin and having an opening in the center thereof for pivotally mounting the same upon the cutting edged shank of the handle of a cutting tool, and each of the said cutting edges conforming to the cutting edge of said shank when turned and aligned therewith.

My invention further consists in forming the shank of said handle with a counter-sunk recess of the same shape as a portion of the said disc, and allowing said disc to be seated and by registering contact to be secured against turning therein, upon the tightening of screw passing through the opening of said disc and in screw threaded connection with the said shank.

My invention further consists in novel features of construction, and combinations and arrangements of elements and parts illustrated in the drawing and hereinatfer more particularly pointed out and claimed.

Attention is hereby directed to the accompanying drawing illustrating a preferred form of my invention in which similar numerals of designation refer to similar parts throughout the several views, and in which Figure 1 is a side elevational view of a roofing or pruning knife and attachment embodying my invention;

Fig. 2 is a sectional view on line 2-2 of Fig. 1, looking in the direction indicated by the arrows, and

Fig. 3 is a sectional view on line 33 of Fig. 1, looking in the direction indicated by the arrows.

2,732,620 Patents-ti Jan- 1, .956

Referring to the drawing, I have there shown a roofns r Pray n halt pmprisih a hat sh nk 4, a h i 5 and a t u -bl de knife 9 di c 6- h s k 4 islems i t e amnion o th of th de of a Pru his .kn e e cept th t' hav ma t m s w at h ke d n Pla e 9 th 11 1 a h P nt th 1 have provided a countersunk recess 7, which recess is h pe o sont m 9 a p rt o of the f o e and f -b a ed kn fe. armin t e ins Prs g h ease 8 9 t e sai hhh i ha ene and i c ve ali nme w th ea h of he cu ting ed s f th .d s ,6 whe thmed t hs t eh the walls 10f sa ses being so losa d ansisha esl s t as hn sh thi e ul As shown, the inset 6 is a thin square-shaped disc of tem ere ste l in the hhit tm sha pe a r wead s a ed paint 19 1, 11 and utwa d p ec ing substantially beyond the periphery thereof, and the uh iq m sh red tmhmks c t n edges 14. 15 an 16, respectively, extending .therehetween. It is secured within the recess 7 by the set screw 17 passing through an opening in the center of said inset, and effecting threaded engagement with the back wall of said recess; but as is obvious may be secured by any suitable means. Preferably, the said cutting edges are curved and the said disc and recess are so shaped and located as always to be turned to bring one of said cutting edges in curved alignment with the cutting edge 8 of the shank 4.

The counter-sunk recess 7, as shown in Fig. 1, is so shaped convexly as to engage one of the said sharpened points of the disc 6, and thereby to prevent the said inset from turning within said recess; but as, is apparent, such recess could be dispensed with, and the multiple bladed disc 6 pivotally mounted directly upon the shank 4, with a stop therein or other equivalent for positioning said disc 6 upon said shank and preventing rotation thereon.

My improved device can be used by the roofer in a horizontal position as is usually the case, or it may be used in vertical position, in which case the clear cutting edge at the bottom of the device could efiectively be used as a utility knife by workman in standing position. Since the multiple bladed disc has four cutting edges, the workman has the equivalent of four cutting knives at his ready disposal, it requiring but a minute to loosen the screw 17, to readjust and turn the disc 6, and again to tighten the said screw, thereby rendering a new cutting edge available. Also the said disc when dull may at any time be replaced easily by another disc with sharpened edges. Also this form of construction, renders it possible to use thinner knives, and thereby much more easily to cut asphalt roofing, than is the case with thicker blades now deemed necessary in cutting such material. While preferably I provide my device with the cutting edge 8 upon the shank 4, in co-operation with the inset 6, this is more particularly for pruning purposes. For cutting roofing, the shank 4 could be of any suitable form and such cutting edge could be dispensed with, and the blades of the inset 6 solely relied upon.

By the words arrow-head shaped point, arrowheaded pointed or equivalent language used in the claims, as applied to the projecting portions of the four-bladed knife or disc 6, I desire to be understood as meaning pointed extensions, each of which is cuneiform in shape and With sloping sides in the same configurative relation with the median line thereof.

My invention may be embodied in other specific forms without departing from. the spirit or essential characteristics thereof. The present embodiment, as above set forth, is therefore to be considered in all respects as illustrative and not restrictive, the scope of my invention being indicated by the appended claims rather than by the foregoing description, and all changes which may come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

What I claim and desire to secure by Letters Patent is:

1. A multiple bladed knife, comprising a handle and secured thereto a flat shank in the form of a blade with a curved continuous cutting edge, said blade having a recess formed in the outer surface of the end portion of said blade, the curved cutting edge of said blade extending to but not beyond said recess; a metallic disc with a plurality of separate uniformly shaped cutting edges symmetrically and sequentially disposed about a common center, each of said cutting edges being curved and terminating in a sharpened arrow-head shaped point projecting outwardly from said center, and each of said edges when registered with the curved cutting edge of said blade forming a curved longitudinal extension thereof; the walls of said recess conforming to the shape of said disc and by registering contact therewith, causing the same to be seated against turning therein; and means for detachably and adjustably securing said disc within said recess so as to allow one of its cutting edges to be 4 in curved alignment with the sharpened edge of said shank.

2. The subject matter of claim 1, the said metallic disc having four curved cutting edges symmetrically disposed about a common center and adjustably disposed so as each to be brought into curved alignment with the cutting edge of said shank, and the walls of said recess conforming to the shape of said disc and permitting the same to be seated against turning therein.

3. The subject matter of claim 2, the sharpened points of the said disc being disposed in pairs in opposite alignment one with the other.

References Cited in the file of this patent UNITED STATES PATENTS

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