GB2233895A

GB2233895A - Insect screen

Info

Publication number: GB2233895A
Application number: GB8916496A
Authority: GB
Inventors: Herman Oskam
Original assignee: Hunter Douglas Industries BV
Current assignee: Hunter Douglas Industries BV
Priority date: 1989-07-19
Filing date: 1989-07-19
Publication date: 1991-01-23
Also published as: GB8916496D0

Abstract

An insect screen comprising an expandable panel structure 16 formed of a plurality of elongate parallel hollow cell structures 22 linked to one another to form the panel, the panel having a movable end rail 14, the cells each having front and rear walls of a mesh material, the front and rear walls of each cell including a longitudinal crease 28, 30, whereby movement of the end rail 14 will cause the front and rear walls of the cells to fold, in concertina fashion, at the creases and the screen can be drawn towards an open position. <IMAGE>

Description

INSECT SCREEN The present invention relates to insect screens for providing protection against the ingress of insects through an opening, such as a door or window opening.

Traditionally such insect screens can be formed using a demountable frame with a mesh material, such as a wire mesh, which is placed over the outside of the door or window opening. In recent times proposals have been made for an insect screen to be formed as a type of roller screen which can be wound up in a conventional roller screen manner if one wishes to leave the door or window opening free.

Such structures are, however, rather bulky and if the door or window opening is large, the bearings and operation mechanism can be particularly cumbersome and expensive.

Further proposals have been made to make such roller screens of a double mesh material, the two sheets of mesh material being joined by cross material, in the manner of the rungs of a ladder. However, while these may provide better protection against the insects, they are even more bulky than single roller screen types of blind.

It is now proposed, according to the present invention, for the insect screen to comprise an expandable blind construction including the plurality of elongate parallel, hollow cell structures linked to one another to form a panel, the panel having a movable end rail, the cells each having front and rear walls of a mesh material, the front and rear walls of each cell including a longitudinal crease, whereby movement of the end rail will cause the front and rear walls of the cells to fold, in concertina fashion, at the creases and the screen can be drawn towards an open position.

Such a structure can be made relatively inexpensively and the mechanism for drawing the panel back can be exceedingly simple and therefore not very bulky.

The movable end. rail may be directly movable by hand to and from the open position. However, it is also proposed that at least two draw cords should be attached to the end rail and pass through all of the cells of the panel, whereby operation of the draw cords will cause the movement of the end rail.

The mesh material may take a number of different forms and the preferably there are 15 to 60 meshes per square centimetre. The material may be of glass fibre coated with a plastics material or it be formed of a material such as polypropylene again itself coated with a suitable plastics material to enable the creases to be formed.

In the preferred construction the creases are arranged so that the material on either side of each crease of the front and rear walls folds outwardly thereby making the drawn back screen more compact than if they were to be folded inwardly. Normally it is preferable that the screen, as viewed from the side, is symmetrical although it is contemplated that the actual structure of the cells could take many forms. In their present preferred arrangement, however, the cells are generally hexagonal in cross section to provide a so-called "honeycomb" panel.

If the screen is to operate satisfactorily, it must be capable of extending over a door or window opening and remain in position even when a wind is blowing. This can be achieved in a number of ways. For example, the screen could have stiffening members placed longitudinally of at least some of the cells, these stiffening members engaging in a channel section side rail of a window. If the screen is to be used for a door, then the end rail will be vertically extending, as will be the cells of the panel, and in this arrangement such stiffening members would engage in a top rail and a bottom rail.

In an alternative arrangement to counteract the effect of wind, one may simply rely on the weight of the end rail, if it is a bottom rail or the end rail could be provided with some form of latch and the draw cords could provide the necessary stiffening.

In order that the present invention may more readily be understood, the following description is given, merely by way of example, reference being made to the accompanying drawings, in which: Figure 1 is an exploded perspective view of one embodiment of insect screen according to the invention; Figure 2 is a perspective view of an insect screen of the invention used to cover a door opening; Figures 3 to 8 are schematic cross sectional views showing portions of further embodiments of screens according to the present invention; Figure 9 is a perspective view of a further embodiment; Figures 10 and 11 show in plan the side sealing arrangement of the construction of Figure 9; and Figures 12 and 13 are views similar to Figures 9 and 10 of a modified construction.

Referring first to Figure 1, there is illustrated therein one embodiment of insect screen 10 according to the invention, this including a head rail 12 mounted using brackets 13, over a window or door opening, a bottom rail 14 and an expandable panel 16 slidable between side rails 18 and 20.

The panel 16 includes a plurality of elongate, parallel hollow cell structures 22 linked to one another, the cells 22 each having front and rear walls 24, 26. The front and rear walls 24, 26 each include a crease 28, 30.

In the construction shown, which is preferred, the creases 28, 30 are outwardly projecting. It can be seen that the top and bottom of the cells 22 each having slid thereinto a stiffening member 32, 34 and this is used to slide into the channel section head rail 12 and bottom rail 14 to secure the panel 16 to these rails.

Lift cords 36, 38 are attached to the bottom rail and pass upwardly through each of the cells and pass over a pulley schematically illustrated at 40 to enable the bottom rail to be raised and lowered.

It will be seen that the side rails 18, 20 each include a web 42, side flanges 44, 46 and inturned rims 48, 50. At least some of the cells 22 have extending longitudinally therethrough a stiffening member, e.g. a strip of aluminium, or the like, indicated by the reference numeral 52, this strip extending slightly beyond the end of the tubular cell structure. The width of the strip 52 is marginally less than the spacing between the beads 48, 50 and thereby the strips 52 can act as guides to prevent the panel 16 from moving inwardly and outwardly should the wind blow when a window is open. Additionally, or alternatively, the bottom rail 14 can be provided with a latch or latches (not shown) to retain the bottom rail in a particular position, usually abutting the windowsill, and the lift cords 36, 38 will then serve the effect of preventing the panel 16 from billowing in the wind.

With reference made to Figure 2, it will be seen that the structure illustrated therein is modified so that the elongate panel 16 is capable of moving in a horizontal direction, rather than in a vertical direction, to act as an insect screen for a door opening rather than a window opening.

Figures 3 to 8 illustrates, very schematically, further structures of insect screen according to the invention and like parts have been indicated by like reference numerals to those of Figure 1.

It will be noted that the various structures illustrated, contemplate the possibilities of using strips; single sheets; multiple sheets and multiple sheets and strips.

Figure 9 illustrates a further construction in which like parts have been indicated by like reference numerals but with the addition of 100. It will be noted that some of the cells 120 have associated therewith a stiffening member 152 which is provided with an end notch 160 of trapezium shape. The cells 120 similarly have trapezium shaped notches formed therein. The stiffening members 152 may float within the cells 120 and be retained in position by the lift cords 136 or, alternatively, they may be secured, e.g. by adhesive, to the cross-members 121 of the relevant cells.

The side rails corresponding to side rails 18, 20 of Figure 1 (not shown here) have, associated therewith, or are alternatively replaced by, trapezium shaped sealing strips 118 of either a resilient or non-resilient material, these being dimensioned so that, with the cells 120 in their normally stretched condition, the edges of the corresponding notches 161 in the cells are in close sealing relationship as shown in Figure 10. It will be seen from Figure 11 that the sealing member 118 subtends an angle a. When the screen is retracted, the development of the notches 161 (Figures 10 and 11) of the ends of the cells 120 subtend an angle p which is larger than the angle a so that there is little or no friction between the cells and the sealing member 118.

The notches 160 in the stiffening members 152 can be chosen to have an angle larger than a, so that there will be no friction with the stiffening member 152. The sealing strip 118 prevents ingress of the insects around the ends of the cells. A particular example of resilient guiding and sealing strips is illustrated in Figures 12 and 13.

In a similar way sealing strips may be mounted in the side rails 18, 20 of the structure of Figure 1, or any of the modifications thereto illustrated in Figures 2 to 8.

In order to reduce the friction during raising and lowering of the blinds such sealing members may be made to be mechanically retractable during the opening and closing movement.

Claims

1. An insect screen comprising an expandable blind construction including a plurality of elongate, parallel, hollow cell structures linked to one another to form a panel, the panel having a moveable end rail, the cells each having front and rear walls of mesh material, the front and rear walls of each cell including a longitudinal crease, whereby movement of the end rail will cause the front and rear walls of the cells to fold, in concertina fashion, at the creases and the screen can be drawn towards an open position.

2. An insect screen according to claim 1, wherein at least two draw cords are attached to the end rail and pass through all of the cells of the panel, whereby operation of the draw cords will cause movement of the end rail.

3. An insect screen according to claim 1 or 2, wherein the mesh material has a mesh size of 15 to 60 meshes per square centimetre.

4. An insect screen according to any preceding claim, wherein the mesh material is formed of glass fibre coated with a plastic material.

5. An insect screen according to claim 1, 2 or 3, wherein the mesh material is formed of polypropylene and coated with a suitable plastics material to enable the creases to be formed.

6. An insect screen according to any preceding claim, wherein the creases are arranged so that the material on either side of each crease of the front and rear walls fold outwardly, thereby making the drawn-back screen more compact than if it were to be folded inwardly.

7. An insect screen according to any preceding claim, which is symmetrical, when viewed from the side.

8. An insect screen according to claim 7, wherein the cells are generally hexagonal in cross-section to provide a honeycomb panel.

9. An insect screen according to any preceding claim, wherein stiffening members are placed longitudinally in at least some of the cells, the stiffening members engaging in a track on each side of the window or formed in a top and bottom rail of a door.

10. An insect screen substantially as hereinbefore described with reference to and as illustrated in Figures 1 and 2 of the accompanying drawings.

11. An insect screen according to claim 10 and substantially as hereinbefore described with reference to and as illustrated in any one of Figures 3 to 13 of the accompanying drawings.