US 2319225 A
Description (OCR text may contain errors)
W 1943 J. J. G REB.E a -rAL v 2,319,225
SUN SCREEN Filed Jan. 1:5; 1941 2 Sheets-Sheet 1 NVENTOR Jail/V M 6251: Mlklfyl. EW/l/d ATTOZNE' May 18, 1943 J. J. GREBE Em 2,319,225
sun SCREEN Filed Jan. 13, 1941 2 Sheets-Sheet 2 j V V INVENTOR JOHN J 6 255! I BY l l Alkliy 5 iW/A i 71/54 Arron E-Y simple operations fr material.
- panying drawings, in which Patented May 18, 1943 UNITED STATES PATENT OFFICE,
SUN SCREEN John A J; Grebe, Midland,
Grand Rapids, Mich., assignors to Ewing Deand Walliley Ewing,
velopment Company, Bay City, Mich., a corpo-' ration of Michigan a Application January 13, 1941, Serial No.,374,194
' 1 Claims.
direct rays of the sun both when the s-u'nis at a high altitude and'an azimuthal angle ro ghly normal to the shade and when the s' n is nearly on the horizon and at an oblique a gfle to. the
screen, and which at\ the same time wil permit materially greater vision directly through the screen than domost conventional shades.
Another object is to provide a screen whichils can bereadily and inexpensively fabricated by,
' om a single piece ,of sheet These and other objects are accomplished in the-'sun-screen of the invention, which consists essentially of a plurality of parallel strips of sheet material spaced at intervals not greatly exceeding'the width of a strip, and spaced paral; lel legs of sheet material inclined to the general plane of the screen and connecting the stripswat intervals along the lengths thereof, as hereinafter described tvith reference to the accom- Figure 1 is an enlarged front elevation of a small portion of a preferred form of the sunscreen according to the invention;
Figure, 2 is a cross-section alang the line 2-2 of Figure 1; 1
Figure 3 is an en of slltted blank us Figuresl and 2;" p
Figure 4 is an enlarged perspective view showing theiblank of Figured partially expanded into the screen of Figures 1 and 2; and v Figure 5 is an enlarged perspective view of an-./
larged plan view of a portion I e'd inmaking the screen of 5 other ,formoi screen according to the "invention.
The sun-screen illustrated ingFigures 1 and 2 is formed by slitting and folding a single sheet of material, as will be explained, and consists of a series of parallel strips 6 of elongated crosssection which are vertically superposed at equal intervals not greatly exceeding, and preferably 5 approximately equal to, the width of a strip, and are inclined, preferably at least 45, tothe general plane of thescreen, i. e. to the vertical. As shown, each individual strip 6 extends horizontally across thescreen and lies in a singlefplane, and is offset regularly in the same direction at equal intervals along its length, as at 1, the distance of offse't'not exceeding about three-fourths the width of the strip, and being advantageously about one-half.such width. The strips 6 are joined together by vertical rows of legs 8 formed of sheet material integral with that oflthe strips,
each leg having a width substantially equal to I the regular olfset distanceof each strip, *1. e. not
greater than about three-fourths the width of a strip, and connecting a front portion 9 Of a strip with the corresponding oppositely offset rear edge ID of an adjacent strip. The rows of legs 8 are ordinarily spaced apart a distancelarge in comparisonto the intervals between adjacent strips.
As will be seen from the drawings, the'legs' 8 areinclined to the general plane of the screen, and are also rather sharply inclined to the strips to which they are attached. The legs in any given row are ordinarily in the saine or in parallel vertical planes, and preferably have their centers all in thes'ame vertical line, in order to give a generally rectangular appearance to the screen. 1 i m While the sun-screen is illustrated with only .two offsets per strip and two rowsof legs, it will be appreciated that it may comprise any number of offsets and corresponding rows of legs, t'o'form a screen of thedesired dimensions. In general, the width of a strip will be from one-eighth to one-half inch, and the distance between rows of legs 7 one-half to five inches," although other sizes are eq all possible. The scr'een is usually fabricated }f thin sheet metal, but may also be formed of 0 her flexible, strong materials, such as synthetic plastic sheet.- I F In making the sun-screen ill strated, thesheet material is first slit to form a i ank, as in Figure 3, which is then formed into e screen. In the slit blank, which is prefera 1y rhomboidal in shape to avoid waste, the sli s are all substantially parallel to one'another', and are disposed on he bias to anedge of the' heet, thebias angle ill being determined as ereinafter explained. As shown, the slits are arranged in a plurality of likeparallel series, as at 12 iand l2. The individual lines within a series are regularly offset a distance which does not exceed aboutthree-fourths the distance between correspond ing' lines'of adjacentserieaand overlapat their offset positions a distance which does not great-,
' ly exceed, and need not equal, the distancebetween corresponding lines of adjacent series. As a result of "this slitting, there are formed parallel continuous regularly olfset strip mem-. bers 6 interconnected at their corresponding oppositely offset portions by leg members 8.
The blank slitted as described is formed into sun-screen by successively displacing each strip member 6 by accurately controlled means, in a direction diagonally downward and backward substantially in the bias direction, 1. e. parallel to the long edge of the strip, thus forcing the strips into vertically superposed parallel planes, and causing the leg members 8 to become sharply inclined to the strips and to the general plane of the screen. A partially folded blank showing two of the strip members already displaced into position is illustrated in Figure 4. The displacement of the strip members 6, and the concurrent formation of the legs 8, may be rendered more accurate by defining on the blank fold lines l3 to mark the point of juncture of the leg members 8 with the strips 6, either'by suitably crimping the blank or by other means. The fold lines II are ordinarily oblique to the long edges of the strips 8 (as at angle II in Fig. 3) and are preferably in the same or parallel planes.
The angle at which the strips 8 are inclined to the general plane of the screen is controlled primarily by the angle H of the fold lines, and to a lesser extent by the bias angle l i. In making the screen, these angles and the various dimensions oi! the strips 8 and leg members 8 are chosen so that, in the final screen, the strips 6 have an inclination capable or providing the desired protection from direct sunlight. The precisechoice of these angles and dimensions is made from mathematical formulas which have been developed from the geometry of the screen and the blank.
In use, the sun-screen is ordinarily mounted in a frame or hung in such manner that the strip are inclined downand outwardly toward the direction of the sun, and that the strips 6 are horizontal. For eastern and western exposures, where the rays 0! the sun are for the most part at an acute angle to the plane of the screen, the screen is also mounted so that the legs 8 face toward the sun. Thus, if the screen in Figure 1 is considered as viewed from outside a window being shaded, it is in position for use in a westerly exposure, the sun being to the right, or south. For an east window, the screen would be inverted, i. e. top for bottom and inside for out, so that the legs face to the left. Likewise,
for certain exposures where it is necessary, seasonal or even diurnal changes in the general direction of incidence of the sun's rays on the screen may be met by inverting the screen, thus aflording protection at all times.
The unusual and advantageous characteristics imparted to the sun-screen of the invention by its regularly oiIset strips 8 and interconnecting leg members 8 may best be understood from the following considerations:
The number or hours during the day in which a shading device 0! the Venetian blind type atfordsv complete shade against the direct rays 0! the sun is relatively small. Now. from the geometry or such a device, it will be evident that, for such devices at most windows, the period of complete shade may be prolonged materially either (a) by rotating the whole shade, in the lane of the window, to bring the sun more nearly into a plane normal to the face 01' the shade and parallel to the vertical center line thereof, e. g. by slanting all the strips downwardly from one end to the other, or (b) by rotating the whole shade about its vertical center line in that direction which will decrease the angle of incidence of the sun's rays on the shade, e. g. by pushing one side of the shade out of the window.
Purely for prolonging the period of complete shade, and without regard to practicability, either or both of these rotation are preferable to the conventional practice of adjusting the strips of the shade to a sharper tilt, since, unlike the latter, they do not reduce the open area of the shade, and hence do not restrict outward vision or exclude ingress of reflected light, Of course, with existing shading devices, the rotations described would be so obviously awkward and difficult as to be impractical.
In the sun-screen of the present invention, however, the structure is divided into many small units in which advantage is taken of both the shade-prolonging rotations discussed, and yet the structure as a whole remains in the plane of the shaded opening and rectangular to it in general pattern and appearance. Thus, as will be evident from Figure l, in any strip 5, each individual element lying between any two legs 8 is rotated slightly in the general plane of the screen. being inclined downwardly from left to right. However, because of the regular ofiset members I, which exactly make up for this downward slant, the entire strip 6, constituting a series of individual strip elements which extend from one end of the screento th other, presents a strictly horizontal appearance. Again, each individual element extends from left to right outwardly from the plane of the screen, but'the offset members in the strip make up for this extension, so that the screen as a whole is substantially in a single plane.
While the use of regularly oil'set strips as described tends toward a longer period of complete shade because 01' the two rotations of the individual shading elements, it will also be evident that if strips were merely thus offset without further structural provision, material leakage of sunlight would occur through the screen at the gaps left at each oflset position. In the screen or the invention, however, the leg members 8 extend fully from the offset at the edge or one strip to the corresponding opposite oflset on the adjacent strip, and thus precisely fill the gap in the shade which would otherwise be present. In other words, the presence or leg members 8 at each offset or each strip not only contributes to the structural unity or the screen, but also is functional to the shading purpose or the screen.
Another screen structure according to the invention which retains the advantageous characteristics Just discussed is shown in Figure 5. This latter screen consists of a series or parallel strips 8 which are substantially identical with the strips as in Figures 1 and 2. However, in the screen of Figure 5, the legs I interconnecting the strips 6 at their oiiset positions are formed of sheet material which is vertically continuous, and are provided at equal interval with slots I8 into which the strips 8 fit. In a slight variation or this structure, the strips need not be horizontally continuous, but may be made up or individual elements secured to the legs and offset regularly. to give a structure substantially identical with that 01 Figure 5.
The sun-screen or the invention, particularly in the preferred embodiment 01. Figures 1 and 2, possesses a number of advantages other than the efllciency or exclusion of oblique rays of the sun already mentioned. The screen may be fabricated by extremely simple means from a single sheet oi. material, and can be made in any desired size. The metal in the screen is not under stress,
having been merely folded into position. The
structure presents only smooth, flat surfaces, and
If desired, it -may be rolled "up for are possible without departing from the inven- ':tion Thus, the screen may be formed of sheet material which is a 'dark color on the top but refiective on the bottom, so'that'the direct rays 'of the sun are absorbed and do not penetrate the screen, butcooler reflected light i'rorntlie near ground' is'refiected inwardly. If desired, the screen maybe fabricated of 'a sheet composed of two materials'of differentcoeiilcients' of expanfinished screenwill automatically vary .with temperaturechanges, thus permitting the'rays of the sun to pass through the screen to -a greater degree when it is cool than when it is hot. Corrugated strips may be provided by using corrugated sheetin making the screen or impressing corrugations in the forming operation, thereby giving added strength to the final screen. Again, the screen may be reinforced vertically, as by rolling or soldering vertical wires into the screen at the offset corners of the strips, or may be edged with a continuous tape or selvage edge secured to or integral with the material forming the individual strips. Such an edge, which is easily made in the plane of the screen during the forming operation, can readily be anchored to frames of any type. and can be rolled or crimped to form seams which permit ready joining of two or more screens to produce a wider structure. These and other variations within the scope of the claims will doubtless occur to those skilled in the art.
It is to be understood that the foregoing description is illustrative rather than strictly limitative, and that the invention is coextensive in scope with the following claims.
We claim: I I
1. In a sun-screen, a plurality of parallel strips of sheet material inclined to the general plane of the screen and spaced at intervals not greatly exceeding the width of a strip, and spaced parallel legs of sheet material inclined to the gen-. eral plane of the screen and connecting the strips at intervals along the lengths thereof.
2. In a sunscreen, a plurality of parallel strips of sheet material inclined to the general plane of the screen and spaced apart at intervals approximately equal to the width of a strip, and spaced parallel legs of sheet material inclined to the general plane of the screen and connecting the strips at intervals along the lengths thereof.
3. A screen according to claim 2 wherein the strips are inclined to the plane of the screen at an angle of at least 45.
4. A screen according to claim 2 wherein the legs are arranged in vertical rows, all the legs in each row being in substantally the same vertical plane.
5. In a sun-screen, a plurality of parallel strips of sheet material inclined to the general plane of the screen and spaced at equal intervals not greatly exceeding the width of a strip, and spaced parallel legs of sheet material integral with that of the strips inclined to the plane of the sunscreen and to the strips, and connecting the front portion of each strip with the rear portion of an adjacent strip at intervals along the length thereof, the width of a leg not exceeding about threefourths the width of a strip.
"6. Ina sun s'creen, a series of parallel vertically superposed horizontally extending series of stripyelements', the individual elements of each horizontal series being inclined to the general plane of the screen and t'othe horizontal and being interconnected in oifsetrelation, and leg members connecting the strip elements of each v horizontal series with the corresponding elements of an adjacent horizontal series.
7. In a sunscreen, a plurality of parallel vertically superposed horizontally extending series of "strip elements, the individual elements of each -'sion,'such as a bimetallic laminat'ed'sheefl inthis case the angle of inclination'of the strips in the horizontal series being inclined to the general plane of the screen and to the horizontal and being interconnected by offset members, the elements and onset members of each horizontal series together constituting a single integral strip lying in one plane, and leg membersi connecting the strip'elements of each horizontal series with the'corresponding elements of an adjacent horizontal series.
8. A sunscreen according to claim 7 wherein the horizontally extending series of strip elements are vertically superposed at equal dis- 'tances approximately equal to the width of a strip element, and wherein the individual strip elements are inclined to the general plane of the screen at an angle of at least 45.
9. In a sun-screen, a series of parallel horizontally disposed strip members which extend across the screen and are offset at intervals along their lengths and are vertically superposed at intervals not greatly exceeding the width of a strip. and legs of sheet material interconnecting the strips at intervals along their lengths.
10. In a sun-screen, a series of parallel inclined strips vertically superposed at equal intervals not greatly exceeding the width of a strip, each strip extending horizontally across the screen in a single plane and being ofiset at regular intervals along its length, and legs of sheet material inclined to the general plane of the screen and interconnecting the strips at the offsets thereof.
11. In a sun-screen, a series of parallel strips of sheet material vertically-superposed at equal intervals not greatly exceeding the width of a strip, each strip being inclined to the general plane of the screen and extending horizontally across the screen in a single plane, and being offset at regular intervals along its length a fixed distance not exceeding about three-fourths the widths of a strip, and legs inclined to the plane of the screen and formed of sheet material iiitegral with that of the strips and connecting the offset portions of each strip with the corresponding oppositely offset portions of the adjacent strips.
12. A sun-screen formed by slitting and folding sheet material and comprising a series of parallel strips vertically superposed at equal intervals not greatly exceeding the width of a strip,
each strip being inclined at least 45 to the general plane of the screen and extending horizontally across the screen in a single plane, and being regularly oiIset at equal intervals along its ularly offset overlapping slits, said slltted sheet thus defining a plurality'ot parallel continuous regularly ofiset strip members interconnected at their corresponding oppositely offset positions by leg members.
15. Abl'ank capable of being formed into a sunscreen comprising a sheet substantially rhomboidal in shape and having therein and at an acute angle to an edge thereof a plurality of like parallel. series of parallel regularly otlset overlapping slits in which the regular offset dis- 20 tance between slits within each series does not exceed about three-fourths the distance between corresponding slits of adjacent series, and in which the distance of overlapping between slits within a series does not greatly exceed the distance between corresponding slits of adjacent series, said slitted sheet thus defining a plurality of parallel continuous regularly offset strip members interconnected at their corresponding oppositely oflset portions by leg members.
16. The method of forming the blank defined in claim 14 into a sunscreen which comprises successively displacing each strip member diagonally downward and backward in the bias direction to force the strips into substantially parallel v planes and to cause the leg members to become inclined to the strips and to the general plane of the resulting screen.
JOHN J. GREBE. WALKLE'Y B. EWING.