US1942542A - Wall-paper trimmer's straightedge - Google Patents

Description

Jan. 9, 1934. F. E. EDGREN ET AL WALL PAPER TRIMMERS STRAIGHTEDGE Filed July 15, 1951 Patented Jan. 9, 1934 UNITED STATES PATENT OFFICE 4 Claims.

Our invention relates to straightedges of the type more especially used by wall paper trimmers; the invention having for its object the provision of straightedges made of sheet metal formed so as not to be of too great weight while at the same time having the required. strength and rigidity to prevent warping.

The invention also has for its object a straightedge which may be easily manufactured at not too great a cost and so formed as to constantly maintain its proper alignment for the true and proper trimming or cutting of the paper or other material with which it is used.

A further object of the invention is the provision of a straightedge whose cutting or trimming side is so formed that a continuous firm holding contact with the material adjacent to the point of cutting will be provided; and furthermore that a true vertical face or side for the cutting edge of the device will be had.

Our invention contemplates an all metal straightedge which, although comparatively light in weight, is so reenforced that bending or distortion through careless handling is impossible.

The above enumerated objects and the advantages of our invention will all be readily comprehended from the following detailed description of the accompanying drawing, wherein:

Figure l is a perspective view of a portion of our improved straightedge.

Figure 2 is a perspective view of a portion or one end of a straightedge showing a modification of the invention.

Figure 3 is a perspective view of one end or portion of another modified form of our improved straightedge.

Our invention contemplates a straightedge wherein the main body portion is formed from a single piece or sheet of metal so constructed as to be self-sustaining; and in the'embodiment shown in Figure 1 the main body 5 is formed from a blank of comparatively thin sheet metal of predetermined length and width; the length of the sheet being substantially in keeping with the length of the desired straightedge, as for example six, seven or eight feet.

The sheet of metal is bent to provide a flat upper surface of comparative width to permit the operators hand to rest thereon in order to hold the straightedge in place; while one longitudinal side is bent downwardly at right angles to the top as shown at 6. In order to provide proper rigidity to this downwardly bent portion and also provide a bearing surface, the lower longitudinal edge of the vertical side 6 is provided with an inwardly disposed flange 7.

The opposite longitudinal side is bent downwardly at right angles to the top to form the vertical side 8, and then laterally inward to form the flat horizontal portion 9, disposed parallel with the top, and the inner longitudinal edge of the portion 9 is then bent upwardly as at 10 and then parallel with the bottom face of the top as shown at 11; and this flange portion 11 is shown secured to the top preferably by spot welding as shown at 12, so as to rigidly secure the entire longitudinal flange 11 to the body portion or top 5.

With the sheet metal bent in the manner shown and described and the flange 11 integrally secured to the lower face of the top, a very rigid non-twisting and self-sustaining straightedge is provided; and with the under-bent portion 9 preferably of considerable width so as to extend beyond the median line of the straightedga'the body portion 5 will not flex through downward pressure thereon.

The flange portion 11 may be riveted in place, but in order to provide a smooth unbroken upper surface, we prefer to spot weld the flange to the bottom face of the top 5.

It will be understood that the vertical sides.

6 and 8 are preferably of equal depth, with the horizontally disposed portions 7 and 9 arranged in the same horizontal plane parallel with the top 5; and as the straightedge is intended for use with the well known types of trimming tools employing a cutting disc or knife carrying shoe or member which has a limited degree of downward movement, the depths of the sides 6 and 8 are ofpredetermined dimensionsfor such use.

One longitudinal side, preferably side 8, is provided with a track member 13, in the nature of an angle bar of non-rusting metal and of sufficient strength, which is intended to receive the usual gauge portion or guide of the cutting tool.

The vertically disposed side of the track mem-,- ber 13 is of transverse width greater than the transverse width or depth of the side 8, so as to permit the lower longitudinal edge of the track member to extend slightly beyond the planeof the portion 9 and at the same time have the leg or horizontally disposed side 14 extend over the top of the body 5 of the straightedge in slight spaced relation therewith, as shown, for the purpose of receiving the guide portion of the trimming device.

We prefer to use an angle bar for the track Furthermore, the use of screws not only would increase the cost of manufacture, but screws are apt .to become loosened and hence would contact with the cutting disc or knife which would not only dull the cutting disc or knife but would also interfere with operation of the trimming device. We therefore prefer to spot weld the vertical leg or side of the track member to the longitudinal side of the body member as-indicated In Figure 2, we illustrate'a' modification of the main body portion of the straightedge, which, like in Figure 1, iscomposed of a single sheet of metal of predetermined length and width to provide the top portion 15, the longitudinal sideswhereof are'both bent downwardly at right angles to the top 15 to provide the vertical sides 16 and 17. The downwardly bent side forming portions are then bent laterally inward to provide the bottom resting portions 13, 19, which, in turn, terminate in the upwardly sloping portions 20', 20 and thence horizontally disposed portions 21.

The portions 21 are intended to extend parallel and in flush relation with the lower face of the top 15, to which they are preferably spot Welded as indicated at 22, so as to provide a smooth unbroken top surface.

, One longitudinal side of the straightedge, like in Figure 1, namely side 16, is provided with the track member 13, similar to the track member heretofore described and preferably secured in place by spot welding the vertical leg or side of the track member, as indicated at 13*, for the reason heretofore stated.

' In Figure 3 we show a further modification also composed of a sheet of metal of predetermined width and length to provide the fiat top 23. One longitudinal side of the sheet is bent downwardly to provide the side portion 24 which is then bent inwardly to provide the horizontal bottom or resting portion 25 whose longitudinal edge is then bent upwardly in the angular manner shown so as to have the immediate marginal portion 26 extend flush with the lower face of the top 23.

The longitudinal marginal portion 26 is also preferably secured to the top 23 by spot welding as indicated at 27.

The other longitudinal side of the blank or sheet of metal is bent downwardly at right angles to the top 23, as shown at 28. This side 28 is preferably of slightly greater vertical dimensions than side 24 and terminates at bottom in the straight edge shown in order to form a continuous binding or holding contact with the material to be trimmed.

The straightedge shown in Figure 3 is intended for use with a knife instead of with a trimmers device and therefore is not provided with the tool guide rail or track as in the previously described constructions, and hence the side 28, which constitutes the cutting or forward side, has been formed as shown and stated.

As the sheet metal blanks are made by forming and not drawn through rollers, as is the case with the brass track members, the bent edges of the metal are more or less rounded, which, of course, would not provide a firm, uniform and more or less sharp edge for holding the material immediately adjacent to the point of cutting. We therefore form side 28 as shown so that the sharp'lower edge of the side 28 will grip the material along the line of cutting.

In order toreenforce this vertical forward side 28 so as to prevent accidental bending or flexing, we show the inner face of the side 28 provided with an angle bar 29, disposed lengthwise of the side and secured thereto so as to have the horizontally disposed leg or side of the angle bar 29 somewhat above the lower longitudinal edge of the side 28, in order not to interfere with the gripping eifect of said edge. In order to leave a smooth unbroken face on the outer side of the cutting side 28, we prefer'to secure the reenforcing bar 29 to the side 28 by spot welding as at 30.

The bottom portion 25 is preferably of such width that its angularl'y bent portion 26 may be disposed substantially at or somewhat beyond the median line of the straightedge.

With the sheet metal bent in the manner shown in the respective figures and the portions which extend parallel with the bottom of the tops integrally secured thereto; it is apparent that a very rigid non-twisting or non-flexing straightedge is provided, as otherwise would be thecase in view of the length and rather narrow dimensions of straightedges; the rigidity of our improved straightedges being due to the fact that the re-' enforcing portions are an integral part of the body to which their free longitudinal edges are in turn integrally secured as described.

By forming the straightedges as shown, comparatively light or thin sheet metal may be em purposes of description and not as terms of limitation as modifications may be made without, however, departing from the spirit of our invention.

What we claim is:

1. A wall paper trimmers straightedge composed of an elongated rectangular single sheet of metal of predetermined width and length formed to provide a fiat top, the two longitudinal sides of the sheet being bent downwardly at right angles to the top to provide vertical sides, at least one of said side forming portions being of greater width than the other and bent inwardly at right angles to provide a horizontally disposed wide bottom portion parallel throughout its width with the top, and the longitudinal marginal part of said bottom portion then bent upwardly and thence laterally parallel and in contact with the lower face of the top and integrally secured thereto to provide a self-reenforcing straightedge wherein the marginal part of said bottom portion is adjacent to the longitudinal center line of the top to reenforce the same.

2. A wall paper trimmers straightedge composed of a single sheet of metal formed to provide a fiat top, the two longitudinal sides of the sheet being bent downwardly at right angles to the top to form the vertical sides of the straightedge and at least one of said side forming portions then bent laterally toward the median line of the device and parallel with the top into a wide flat bottom portion spaced from the top, with the marginal portion thereof thence bent upwardly and laterally parallel with the lower face of the top portion adjacent to the longitudinal center of the top to which said marginal parallel portion is rigidly secured.

3. A wall paper trimmers straightedge composed of a single rectangular sheet of metal formed to provide a horizontal portion coextensive with the width of the straightedge, the two longitudinal sides of the sheet being bent at right angles to the horizontal portion to form the vertical sides of the straightedge and the longitudi-- nal marginal portions of the two side forming;

portions then bent laterally toward each other at. right angles to the sides into horizontal portions arranged parallel with the first mentioned horizontal portion, and at least one of said horizontal marginal portions arranged in bearing relation with the first mentioned horizontal portion, to provide a self-sustaining straightedge.

4. A wall paper trimmers straightedge composed of a single rectangular sheet of metal formed to provide top, bottom and longitudinal side portions, the side portions being at right angles to the spaced apart top and bottom portions, with a part of the bottom portion arranged to support the top portion adjacent to the median line of the straightedge.

FRED E. EDGREN. ROY A. EDGREN.

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