US2070190A - Sickle - Google Patents

Description

Feb. 9, 1937.

T. E. WELLS 'SICKLE Filed Feb. 11, 1935 2 Sheets-S heet 1 INVENTOR 7mm; [0mm] M1 L6 BY CZMV-WMZ ATTORNEYS Feb. 9, 1937.

3i FileQ Feb. 11, 1955 T.E.VVELLS SICKLE 2 Sheets-Sheet 2 INVENTOR 7/70MAJZ0M44/P0 WELL;-

- "3 MW+ M ATTORNEYS Patented Feb. 9, 1937 PATENT OFFICE SICKLE Thomas Edward Wells, Haydenville, Mesa, asslgnor to The Ezykut Tool Corporation, Northampton, Mass., a corporation of Massachusetts Application February 11, 1935, Serial No. 5,949

2 Claims.

This invention relates to an improved sickle having a cutting edge composed of a plurality of safety razor blades arranged in uninterrupted exposed portions.

Another object of the invention is to provide a sickle of the class described in which the razor blades are so mounted as to present a cutting edge of saw-toothed shape.

Another object of the invention is to provide a holding means of improved construction for the blades.

A further object is to provide a sickle of the class described of generally simplified and improved construction, susceptible of manufacture in quantities at low unit cost and providing a cutting tool capable of giving very effective service. I

Other objects will appear as the detailed description proceeds and will be pointed out in the appended claims.

The invention will be disclosed with reference to the accompanying drawings, in which:

Fig. 1 is a small-scale, exterior elevational view of a sickle embodying the invention;

Figs. 2, 3 and 4 are sectional views taken on the lines 2-2, 3-3 and 4-4, respectively, of Fig. 1;

Fig. 5 is a cross sectional view of the clamping plate;

Fig. 6 is a full size view of the sickle with the clamping plate removed and the handle broken away; and

Fig. 7 is an edge view of the sickle, partially assembled.

Referring to these drawings; *the sickle includes a holder I0, in which a plurality of safety razor blades II are mounted, a clamping plate I2 superposed on the blades and suitable means, as for example the knurled head screws I3, for

drawing the plate against the blades and clamp- Y ing them between the plate and the holder. In

addition, any suitable form of handle is provided,

such as the foldable handle I4. As shown herein, the holder, plate and handle are metal stampings and the handle is pivoted to the holder at I5,the part I5 being a rivet which serves to fasten the parts together. For locking the handle and holder against relative pivotal movement, a screw I6 is passed through the overlapping parts of the handle and holder and a thumb nut I6 applied to the screw serves-to draw said parts together. The thumb nut and screw are easily removable, whenever it is desired to fold the handle and holder together.

Obviously, any I (Cl. 30-9) I other means may be provided for locking the handle and holder against pivotal movement and, insofar as the present invention is concerned the handle does not need to be foldable.

This invention is concerned with the mountin of the safety razor blades. A most important characteristic of the arrangement is that there is no overlapping of the blades in their exposed portions, i. e., those portions exposed beyond the substantially coincident inner edges of the superposed members II) and I2. To secure this result, recourse is had to the saw-toothed arrangement of blades shown in Fig. 6. Preferably, also, means are provided to positively hold each blade in the proper predetermined position necessary to secure. the result described, although it is within the scope of the invention, but deemed less desirable, to rely solely on the clamping pressure of the members I0 and I2 to hold the blades from displacement from angular predetermined positions in which they have been placed.

Referring to Fig. 6, the holder I0 is indented at spaced intervals longitudinally thereof to form, on the razor blade receiving surface of the holder, upstanding projections I I of circular cross sectional shape. One such projection is provided for each razor blade and each closely fits the central hole in the razor blade I I. Adjacent each such projection H is an upstanding projection I8, preferably formed by striking up portions of the metal from the holder. The projections I8 are roughly square or rectangular and at least have two parallel sides I9 which engage the sides of, and closely fit inone of the longitudinal slots 20 in the razor blade. so disposed as to compel the blade II to lie at the desired angle, for example substantially the angle shown in Fig. 6. It is preferable also to have the projections H or I8, either or both, fit so closely in their respective openings in their razor blade that the blade, whenput in place and manually pressed down toward the holder I0, will be frictionally held in position, thereby facilitating the assembly of parts. Certainof the projections I1 have perforated tops, forming hollow hubs which are interiorly screw threaded to receive the screws I3.

The invention is not dependent on the exact arrangement disclosed of the projections l1 and IB. The described arrangement has been adopted to suit the particular style of blade disclosed and can obviously be varied, as required, to suit blades of other types. With any given type of blade, one or more projections, equivalent to I! or I8, can readily be provided at the proper locations on holder II] to fit in the aperture or apertures of the blade and hold it against turning in the desired predetermined position.

For retaining the blades in place on holder III, the clamping plate I2 and screws I3 are provided.

These parallel sides I9 are This plate alone could be 'i1S8d to retain the blades but, obviously, it is better practice and therefore more desirable to provide the additional means, comprising projections I1 and it. This plate H2 in common with the holder ill preferably has the saw-toothed inner edge illustrated, although this is not necessarily essential for all purposes. It isdesirable, however, because the teeth such as 2i, serve to support the blades ii except for a short exposed portion. Also, to effectively support the blades, the contour of the inner edge of the supports (members it and i2) ought to conform incontour to the cutting edge, which in this instance is saw-toothed. Therefore, the inner edge of each member ill and 82 should be saw-toothed. The exposed part oi. each blade is thus of uniform width from one end to the other and thus of uniform flexibility.

The clamping member 92 is preferably not perfectly fiat. As viewed in cross section, it has a struck up rib 22, which serves to stifi'en the plate and the concavity along its inner face provides I the clearance necessary to receive theprojections I1 and it. Also, the plate is so formed, as shown in somewhat exaggerated form in Fig. 5, that there is a bearing line 23 along the outer edge of the concavity and another bearing edge 26 along the inner and serrated edge of the plate. Between these bearing edges 23 and 2a, or lines of contact with the blades, the plate is bent upwardly slightly. Thus, when the screws l3 are tightened, the edge 23 will press on the blades ll near the outer edges of slots 20 and also the edge 2 will press on the blades near their outer and cutting edges. By jamming the screws down the plate, between edge 25 and the concavity, may be sprung inwardly and pressed down to bear on the blades. The spring pressure of the plate i2, when thus pressed down, tends like a spring washer would, to prevent screws 53 from working loose. But the more important thing is to insure a close grip on the bladesbetween the members ill and i2 along their outer edges to prevent grass from lodging therebetween as well as to insure proper and adequate support at this critical location.

The clamping plate, as viewed in longitudinal section, preferably is likewise not perfectly flat but rather it is bowed upwardly. After one screw it is applied at one end of the plate, it will be found that the other end of the plate lies materially above the holder as shown in Fig. 7. It is necessary then, as succeeding screws 43 are applied, to spring the plate downwardly and this arrangement insures a substantially uniform pressure on the blades i i from one end of the holder to the other.

The holder I0 may, and desirably does, have an upturned marginal flange 25 along its outer edge. This flange serves to stiffen the holder and gives it a finished and attractive appearance. This flange is not, however, indispensable.

' It should be noted that after the cutting edge has become dull, a new edge may be secured by reversing the blades so that the edge of each that was formerly concealed, becomes exposed. Actually, the greater part of the cutting is done by in the outer most position. Actually, as a pracical matter, four cutting edges can be secured from one set of blades.

With a. cutting tool made up of a plurality of cutters, such as razor blades, it is almost necessary that successive blades overlap in part, at least to a small degree. However, if the overlap of the blades occurs in the cutting edge of the tool, it has been found that serious trouble lievelops. Grass will become lodged between the overlapped parts of the blades and unless removed, which is inconvenient and annoying, will destroy the effectiveness of the tool. At some places along the edge it will out well, while at others where grass has lodged as described, it will not out well atall. The present arrangement avoids any overlap of the blades, not only in the cutting edge but in the exposed parts of the blades. All overlapped parts of the blades lie between the 'members' i0 and i2 which clamp them and it is virtually impossible for blades of grass to become caught between any two superposed parts of this cutting tool. Aside from overcoming the difiiculty, above set forth, the peculiarly shaped cutting edge has proved exceedingly efiective in use.

The invention has been described herein, in an embodiment at present preferred, for illustrative purposes. It is recognized that many variations will readily occur to those skilled in the art having for their object obtaining of the advantages herein set forth in a structure differing specifically from that disclosed. It is therefore the intention to have the scope of the invention defined by the appended claims.

What I claim is:

1. A sickle, comprising, a holder having a curved outer edge and a serrated inner edge roughly paralleling the curvature of the outer edge and having a series of longitudinally-spaced, relatively short, substantially radial portions and a series of relatively long portions, each long portion connecting the innermost extremity of one said radial portion to the opposite extremity of the next adjacent radial portion, a plate superposed on the holder and having a correspondingly formed inner edge, the short and long portions of which coincide with those of the holder, and a plurality of blades clamped between said bladeand holder each having'its cutone face thereof with the ends of successiveblades of the series overlapping, a plate superposed on said blades, and means to draw the plate and holder together to clamp the blades therebetween; a portion of each blade, including a cutting edge thereof,-projecting outwardly'beyond one edge of said holder and plate and exposed; one end of the cutting edge of each blade being laterally offset from the adjacent end of the cutting edge of the next succeeding blade of the series sufliciently so that the overlapped portions of the blades lie entirely between the plate and holder and so that the exposed portions of the blades do not overlap.

THOMAS EDWARD WELLS.

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