BACKGROUND TO THE INVENTION

THIS invention relates to a window screen of the type which is movable in order to vary the exposed area of a window.

Generally there are two kinds of popular window screens. The first comprises a conventional curtain which is supported on rails above the window and which is movable back and forward to either reduce or increase the exposed area of the window. The second type of window screen comprises a blind type of screen in which the screen is supported above the window and the lower edge of the screen can be lowered to reduce the area of exposure of the window. This type of line which may comprise a roller blind or a roman blind is advantageous since the full width of the window can be shielded by the blind down to whatever level is required. Thus, full exposure of the window can be obtained by lifting the blind to the top of the window and the window can be fully shielded by dropping the blind to the bottom of the window.

A problem arises when it is desired to have a curtain or blind in a half open position in order to admit light through the window or to allow someone on the interior side of the window to look out through the window and yet maintain a degree of privacy. It is particularly so where the window is of floor to ceiling height or where the window is at an elevated position. Normally the view through a window will be best through the upper half of the window and this is the half of the window which is desirably open. However, with a blind of the aforementioned type in the half open position the upper half of the window is blocked off by the blind thereby blocking off the view. In addition, where the window is at an elevated position even if the upper half of the window is blocked off by the blind privacy on the interior side of the window will not be achieved since outsiders will be able to look through the lower half of the window directly into the room on the inside of the window. Thus if privacy is required it is necessary to close off the entire window thereby cutting out exterior light and blocking off any view.

SUMMARY OF THE INVENTION

According to the invention there is provided a window screen comprising, a sheet of flexible relatively non-transparent rectangularly shaped material having a length and a width, an upper edge and a lower edge and a pair of side edges, support means for supporting the sheet generally co-planarly with a window, and raising and lowering means connected at least to said upper edge for raising and lowering the upper edge relative to the lower edge whilst maintaining the upper edge in a generally horizontal orientation to thereby expose a greater or lesser area of said window, said upper edge

being securable relative to the window in a plurality of different selected positions.

The window screen may be adapted to move between a lower position in which said upper edge is at or near the bottom of a said window, and an upper position in which said upper edge is at or near the top of said window. The window screen is preferably securable at any intermediate position between said lower and upper positions. The window screen may be raisable to a position in which the lower edge thereof is above the lower edge of the window.

The raising and lowering means may comprise at least one and preferably a pair of strings connected to said upper edge and adapted to pass over respective rollers mounted at or near the top of a window. The roller or rollers may comprise a rolling bar which is adapted to be mounted via suitable brackets above the top of a said window.

The upper edge may have a rigid support rod extending at least a major portion of the way across the width of the sheet. There are preferably a plurality of parallel rods extending across the width of the sheet, each of said rods being connected at opposite ends thereof to a generally vertical guide. The guide may comprise vertically extending taughtly strung lines to which the ends of the rods are slidably connected. The rods may be longer than the width of the sheet so that the ends of the rods extend a short distance beyond each side edge of the sheet. A pair of support brackets may be provided towards the lower part of the window on opposite sides of the rods will be supported. The support brackets may take various forms and may be configured so as to fold the sheet into neat folds as the sheet is collapsed

downwardly with the said upper edge moving from its upper position to its lower position.

Embodiments of the invention are described in detail in the following passages of the specification which refer to the accompanying drawings. The drawings, however, are merely illustrative of how the invention might be put into effect, so that the specific form and arrangement of the specific features shown is not to be understood as limiting on the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 shows a perspective view of a window with a window screen fitted thereto;

Figure 2 shows a side view of a second embodiment of the invention;

Figure 3 shows a side view of a third embodiment of the invention; and

Figure 4 shows a side view of a fourth embodiment of the invention.

DETAILED DESCRIPTION

As shown in Figure 1 , a window screen 10 is in the form of an inverted "roman blind", that is to say, it is a blind which moves upwardly in order to close off a window opening 12 and can be distinguished from conventional roman blinds which move downwardly from the top of the window 14 towards the bottom 16 thereof.

A screen 10 is formed of a sheet 23 of fabric or like material having an upper edge 18 and a lower edge 20 and side edges 22. The upper edge 18 has a rod 24 fitted thereto which, in the operative orientation, is parallel to the upper edge 14 of the window opening. The sheet 23 has a series of pockets therein (not shown) into which rods 26 have been inserted, the rods 26 being parallel to the upper rod 24.

The upper rod 24 has a raising and lowering mechanism 28 connected thereto which supports the upper rod 24 and which is used to move the upper rod 24 up and down thereby increasing or decreasing the extent to which the screen 10 covers the window opening 12. The mechanism 28 comprises a pair of strings 30 which pass over rollers 34. The strings 30 will be pulled together to keep the rod 24 horizontal and parallel with the upper edge 14 of the window opening. The strings 30 have a tie bracket 36 located on one side of the window openings 12 so that the strings 30 can be fixed in any position. Thus, the screen 10 can be raised or lowered to a selected position and then the strings 30 tie to the bracket 36 to secure the screen in the selected position.

A pair of rod support brackets 38 are provided on either side of the window

openings near the bottom 16 of the window openings onto which the rods 26 will rest when the screen is lowered from its fully closed to its open position. The rods 26 extend beyond the side edges 22 of the sheet 23 so that the sheet 23 will fit between the rod support brackets 38 whereas the ends of the rods 26 will rest on the brackets 38. This arrangement will ensure that the sheet material folds itself into loops 40 which are suspended from the brackets 38.

It will be apparent that there could be various different mechanisms for raising and lowering the screen 10 as well as different arrangements for gathering and folding the loops of the screen material which arise as the screen is lowered. Figures 2 to 4 depict different embodiments. Figure 2, for example, shows a screen 50 which has an upper edge 52 and a lower edge 54. Rods or rings 56 are fitted to the screen at evenly spaced positions intermediate the upper edge 52 and the lower edge 54. A taught guide line 58 is suspended between the top and the bottom of the window openings. The rods or rings 56 have holes therein through which the guide line 58 passes. A raising and lowering string 60 is provided which is attached to the upper edge 52 of the screen. As the screen is raised or lowered the rings and rods slide up the guide line 58 thereby ensuring that the screen remains centrally located in the window opening as well as ensuring that as the screen collapses to the condition shown in Figure 2 the screen material will form loops 62 of material which stack neatly one on top of the other.

The embodiment shown in Figure 3 of the drawings is similar to that of Figure 1 but depicts the manner in which the rods 26 rest on the side bracket 38 to form the loops of sheet material 40.

The embodiment shown in Figure 4 of the drawings has a somewhat different arrangement. In this embodiment the loops of material 60 are folded generally horizontally by means of a guide mechanism 62. Alternate rods 64 and 66 have ends of different diameters and the guide mechanism 62 is adapted to guide larger diameter rods 64 to one side and the smaller diameter rods 66 to the opposite side. The guide 62 includes a gap 68 through which the small diameter rods 66 will pass but which the large diameter rods 64 will not pass. Thus, the rods sliding down inclined surface 70 will be selectively allowed to pass through the gap 68, with only the smaller rods 66 passing through the gap whereas the larger diameter rod 64 travel to the end 72 of the inclined surface 70 to thereby form a neat stack of loops 60. The guide 62 is thus not unlike a coin selector as may be found in coin operated mechanisms.

Clearly the invention is not limited to any one of the embodiments depicted in the drawings. Various different arrangements for neatly containing and folding the collapsing sheet are possible and the embodiments described depict only a few of the possibilities. Likewise, the means for raising and lowering the screen can vary from that described therein as can the guide mechanism for guiding the edges of the screen relative to the window opening. The means for raising and lowering the screen can be independent of any guide means or alternatively may incorporate the guide means. The guide means does, however, serve to centre the screen properly with respect to the window opening.

It will be appreciated that with the screen in a semi-open position natural light will reflect from the sky downwardly into a room through the exposed portion of the window whereas the interior of the room will be to a large

extent shielded from view by the screen. Thus, although light is allowed to enter into the room the privacy of the interior of the room is maintained. This is particularly important for rooms which are at an elevated position. Persons outside an elevated room would be looking upwardly and would have their view of the interior of the room blocked by the screen. Of course, where it is desired to have total privacy within the room the screen would simply be lifted up so as to close off the entire window.