There are many types of retractable awning for extending a screen over an outdoor area so as to provide protection from the sun and/or rain. The most common type is the folding arm awning in which the awning screen is attached to folding arms which are in turn attached to a support structure, such as a building facade. The awning screen is extended by unfolding the arms to project out from the building facade. Another type of awning has support structures (which may be rigid or flexible) running in the direction of extension and which support the awning screen as it is extended from the retracted to the extended position.

Some awnings are designed simply to provide shade, i.e. protection from the sun. The fabric of such screens does not need to be waterproof and so it can be made from a light weight material. A porous mesh material can be used to provide adequate shade protection, but such a material obviously provides little rain protection. Other awnings are designed also to provide protection from rain (or other precipitation) and such awnings therefore have a waterproof screen.

However, waterproof screens are necessarily heavier and less permeable and thus impede the flow of air under the awning to a certain extent. On a hot day with little air movement, such a screen traps air under the screen and that area can thus become less comfortable.

According to the invention, there is provided a retractable awning comprising at least a first screen and a second screen, each of which is extendible between a retracted position and an extended position; wherein the awning is arranged such that the second screen is extendible over or under the first screen.

Viewed from an alternative aspect, the invention provides a retractable awning comprising at least a top screen and a bottom screen, each of which is extendible between a retracted position and an extended position; wherein the awning is arranged such that the top screen is extendible over the bottom screen and/or the bottom screen is extendible under the top screen.

With this dual screen arrangement, the awning can have two different fabrics arranged to cover (i.e. to provide protection for) a common area. Having two screens allows the awning to use screens with different fabrics which can be selectively deployed according to the conditions and according to the desires of the users. For example, one screen may be a lighter weight fabric (such as a mesh or net) which provides favourable protection from the sun without trapping air, while the second screen may be a heavier waterproof fabric capable of providing rain protection when required, but which need not be deployed when it is not required.

The first screen and the second screen may overlap only partially in terms of their maximum deployment (maximum extent), but preferably they are designed essentially to cover the same area, i.e. they are designed with a substantially complete overlap in their potential deployment area. It will be appreciated that the potential deployment of the two screens will not necessarily coincide exactly, for example the screens may be of slightly different sizes. One screen may have a slightly larger width or length than the other, but the two screens will still cover substantially the same area, i.e. when both screens are in their positions of maximal deployment, the screens will preferably overlap over the majority of their areas, for example over at least 80%, preferably at least 90% of their areas.

The invention may allow one screen to be deployed first and then the second screen to be deployed either over the top of the first screen or underneath the first screen. Of course both screens can be deployed simultaneously if desired.

Preferably the two screens are electrically driven and both screens are controlled from a single control unit which is communicatively coupled to the motors for both screens. The control unit can preferably extend and retract each screen individually or can extend and retract both screens simultaneously. The control unit may be a fixed unit, e.g. attached to a wall, or it may be a remote control unit, e.g. a handheld remote control. A hand-held remote controller may send signals direct to the motors or it may send signals to another controller from which the motors are controlled. Preferably the first screen is substantially aligned with the second screen in the direction perpendicular to the direction of extension, i.e. the two screens are arranged to extend in parallel directions so that, when both are extended, the sides of the first screen are parallel to and in close proximity to the sides of the second screen.

In certain embodiments, the first screen and the second screen could be mounted at opposite ends of the awning, and be arranged to extend towards each other (i.e. in parallel, but opposite directions), with the second screen arranged to extend over the first screen. However, in other embodiments, the first and second screens may be arranged to extend in the same direction. In such arrangements the two screens are stored at the same side of the screen when they are not in use. The first screen and the second screen are preferably independently movable. In other words, the first screen is capable of being moved without inducing movement in the second screen and the second screen is capable of being moved without inducing movement in the first screen. It will be appreciated that in some embodiments (as described below), it will be necessary to move one screen in order to allow greater movement of the other screen, but both screens are still separately controlled (although preferably they are both controlled by the same control unit).

When not in use, the screens need to be stored. The screens may be foldable in a concertina fashion so that the folds of fabric are gathered at one end of the awning when the screen is not in use. Alternatively, a screen may be stored on a storage roller mounted at an end of the awning. The screen is attached to the storage roller and is wound up around the storage roller when it is not in use. Storage rollers are preferred in some embodiments because they are particularly suited for creating and maintaining tension in the screen fabric while it is in a deployed state or during deployment or retraction. To create tension, the storage roller is simply driven so that it pulls against a force acting on the leading edge of the screen. For example, if a driving force is applied to the leading edge to extend the screen, the storage roller can be controlled to resist that force and to control the speed at which fabric is paid out. Likewise, during retraction, the leading edge is provided with resistance so that tension is created when the storage roller is driven to roll up the screen. Storage rollers may be used for the first screen or the second screen or both.

Storage rollers are particularly well suited where the problem of creating and maintaining tension is more significant. In some embodiments a storage roller may be used for waterproof fabrics, but this need not always be the case. Lighter fabrics for shade only may use a storage roller or may be stored in another simpler fashion. In addition, storage rollers require less space to store the fabric than fabric stored in concertina fashion. The latter also require perpendicular slats spaced at regular intervals that need to be supported. Therefore, each system has its own set of advantages and disadvantages and each one can be used depending upon the circumstances.

In some preferred embodiments, the second screen extends from a rotatable storage roller disposed at one end of the awning and the second screen is wound up on said storage roller when not in use. In other preferred embodiments, the second screen extends from a folded concertina disposed at one end of the awning and the second screen is folded up in concertina fashion when not in use.

In some preferred embodiments the first screen also extends from the same end of the awning as the second screen.

The first screen may be stored wound up on a storage roller when not in use.

Equally, the first screen may be folded in concertina fashion when not in use. Both the upper and lower screens may use either a storage roller arrangement or a folding/concertina arrangement according to the circumstances of the particular installation.

The screens may be movable with respect to the support elements in various ways. For example, the screens may be attached to loops of flexible cable or rope (or similar) that are disposed around pulleys and driven so as to extend or retract the screen. However, in preferred embodiments, a leading edge of the first screen and a leading edge of the second screen are movably mounted to the longitudinal support elements such that the screens move with respect to the longitudinal support elements during extension and retraction. With this arrangement, the screens can be held in place by holding them with respect to the longitudinal support elements, e.g. by friction or by clamping, gripping or braking. This provides a firm engagement between the two components and allows high tension to be created and maintained in the screens. High tension is particularly important in larger screens where the heavier weight of the large screens has a tendency to sag if inadequate tension is provided. With a dual screen arrangement where one screen is extendible above the other screen, tension is also very important as if the upper screen sags enough to contact the lower screen, then movement of one screen with respect to the other will lead to friction between the two, adding strain to the drive system and leading to wear of the fabrics. However, when the two screens are stationary, the lower screen (usually for shade) can be used to support the weight of the upper screen (usually for rain and, therefore, it becomes heavier) if required. In some preferred embodiments, the first screen and the second screen are mounted to the same longitudinal support elements and the first screen is mounted to each longitudinal support element at a position closer to the front of the awning than the position at which the second screen is mounted. This arrangement has the advantage of using only a single set of longitudinal support elements for both screens. Both screens are movably mounted to the same supports and move with respect to those supports during extension and retraction. As both the first screen and the second screen are mounted to the same support elements, the screens must be arranged into a front screen and a rear screen, i.e. one must be mounted to the supports in a forward position and the other mounted behind, i.e. in a rearward position. The rearwardly mounted screen cannot be deployed to a greater extent that the forwardly mounted screen as it is mounted behind and cannot overtake the forwardly mounted screen. However, the forwardly mounted screen can be deployed to any desired extent without deploying the rearwardly mounted screen. The rearwardly mounted screen can be independently driven and deployed to any position up to the extent of the forwardly mounted screen. This arrangement works well when the awning has one screen for shade protection and one screen for rain protection. The shade protection screen is arranged in the forwardly mounted position and can be deployed on its own without deploying the rearwardly mounted waterproof screen. However, if rain protection is desired, then both screens are deployed. The second screen need not be deployed to the same extent as the first screen, thus defining two distinct regions - one with just shade protection, the other with both shade and rain protection.

The two screens can be arranged in a number of ways with respect to the support elements and each other. For example, the forwardly mounted screen can be the uppermost screen, with the rearwardly mounted screen being deployed below it, or the forwardly mounted screen can be the lowermost screen with the rearwardly mounted screen being deployed above it. The latter arrangement is preferred where the rearwardly mounted screen is waterproof, as it then shields the fabric of the non-waterproof screen, preventing it from soaking up water with the associated increase in weight and required tension.

In some preferred embodiments, both the first screen and the second screen are arranged to hang below the longitudinal support elements. This arrangement minimizes the possible interaction between the screens and the support elements. Contact between the screens and the support elements can lead to unwanted friction and thus increased strain and wear in the system. Also, if the screens have a width greater than the separation of the longitudinal support elements then the longitudinal support elements will be hidden from view from beneath the screens. This is more aesthetically pleasing for users of the awning when they are under the screens.

In other preferred embodiments, the first screen is arranged to hang below the longitudinal support elements and the second screen is arranged above the longitudinal support elements. Arranging the screens either side of the longitudinal support elements increases the separation between the screens and thus minimizes interaction between the screens, even when one of them sags towards the other. Locating the second screen above the longitudinal support elements also allows the second screen to provide protection (e.g. rain protection) to the support elements when it is deployed.

In alternative embodiments, the first screen may be mounted to a first set of longitudinal support elements and the second screen may be mounted to a second set of longitudinal support elements. This provides greater flexibility of deployment of the two screens. As each screen has its own support elements, it can move completely independently of the other. Either screen can be deployed to a greater extent than the other as there is no restriction on the relative positions of the leading edges of the screens on the support elements. With this arrangement, the first screen (e.g. a shade-only fabric) can be retracted when the second screen (e.g. a rain fabric) is deployed (or vice versa), thus storing and protecting the first screen while the second screen is deployed. However, if both screens are desired simultaneously, that is also possible. Again, the area being covered by the screens can be divided into two regions, one covered by both screens and the other covered by just one of the screens (this can be either one of the screens).

With separate support elements for each screen, the two screens can be deployed at opposite ends of the awning and can be extended in opposite directions. With this arrangement, the area can be covered by either one of the screens or fully covered by both. In intermediate deployments, one screen can be deployed fully and the other partially, thus creating two zones of differing protection beneath the screens, or both screens can be partially deployed, thus creating three zones of differing protection beneath the screens (one zone protected by one screen only, one zone protected by the other screen only, and a third zone in between which is protected either by both screens or neither screen).

Separate longitudinal support members may be provided in a rigid support framework by providing separate guide rails in side supports (these may be separate guides in a single support or they may be completely separate supports). In some embodiments, the longitudinal support elements may be flexible, e.g. they may be wires, cables, ropes, straps, etc. In the case of longitudinal flexible support elements, both screens may be mounted to the same longitudinal flexible support elements (or set of such elements), or a separate longitudinal flexible support element (or set of such elements) may be provided for each screen.

Typically, a support element (rigid or flexible) is provided at each side of the screen, but more or fewer supports may be used if desired.

In the case of longitudinal flexible elements, these are preferably arranged one above the other so as to minimise contact between the two screens during deployment and retraction, but they may also be deployed side by side if desired. Additionally, it is possible to have one set of ends of the longitudinal flexible elements mounted one above the other, while the opposite ends of the longitudinal flexible elements are mounted side by side.

Preferably the second set of longitudinal support elements is arranged at a greater height than the first set of longitudinal support elements.

Again, the arrangement of the screens with respect to the support elements can be selected according to the circumstances. In some preferred embodiments the first screen is arranged to hang below the first set of longitudinal support elements and the second screen is arranged to hang below the second set of longitudinal support elements. This allows the support elements to be hidden from view as well as reducing the potential interaction between the support elements and the screen which hangs from them.

The screens may be made from a variety of different fabrics. For example, different levels of shade may be used, e.g. different weights of materials such as an open mesh through to densely woven fabrics, or with different levels of translucency or opacity. Different colour fabrics may be desired for different lighting levels or environments. The dual screen arrangement allows these different fabric options to be selected or mixed within a single awning apparatus. In some preferred embodiments the second screen is waterproof and the first screen is not waterproof.

It will be appreciated that while some preferred embodiments use two screens, the apparatus can easily be extended to operate with more than two fabrics if desired. For example several different levels of shade and/or waterproofing can be provided and combined with the use of more than two screens.

Preferred embodiments of the invention will now be described, by way of example only, and with reference to the accompanying drawings, in which:

Figure 1 shows a first embodiment with a rigid support structure;

Figure 2 shows a second embodiment with a rigid support structure; Figure 3 shows a third embodiment with a single set of flexible supports;

Figure 4 shows a fourth embodiment with a single set of flexible supports; and Figure 5 shows a fifth embodiment with two sets of flexible supports. Figure 1 shows an awning 100 in which two screens 10, 20 are extendable with respect to a support structure 30. The support structure 30 is a rigid support structure comprising two rear vertical supports 31 and two front vertical supports 32. At each side of the awning, extending from a rear support 31 to a front support 32 is a horizontal side support 33. It will be appreciated that supports 31 , 32, 33 need not be perfectly horizontal or vertical. For example, the side supports 33 may slope downwards from the rear supports 31 towards the front supports 32 so as to facilitate drainage of water from the surface of the screens 10, 20.

Two screens, namely a first screen 10 and a second screen 20 are provided. The first screen 10 has a leading edge 1 1 and a trailing edge 12. The trailing edge 12 is attached to the rear portion of the awning support structure 30 and the leading edge 1 1 is extendible along the side supports 33 so as to extend or retract the screen 10. In its retracted state, the screen 10 is folded up in a concertina fashion, while in the extended state, the screen 10 is substantially flat and horizontal (or inclined to the horizontal for drainage as described above). The screen 10 is movably mounted to the side supports 33 at several points along its length so that the screen 10 folds up between these points when it is retracted. The leading edge of the screen 10 may be extended manually or via one or more electric motors (not shown). Motors may be provided on the leading edge 1 1 or may be provided elsewhere on or near the awning apparatus 100 and attached to the leading edge 1 1 so as to cause the leading edge 1 1 to move with respect to the support structure 30.

The second screen 20 has a leading edge 21 and a trailing edge 22. The trailing edge 22 is attached to a storage roller 23 located adjacent to the rear supports 31 . The leading edge 21 is extendible along the side supports 33 so as to extend or retract the screen 20. In its retracted state, the screen 20 is wound up onto the storage roller 23, while in the extended state, the screen 20 extends substantially horizontally (or inclined to the horizontal for drainage as described above) out from the storage roller 23 towards the front supports 32. The leading edge 21 of the screen 20 is movably mounted to the side supports 33 and may be extended and retracted manually or via one or more electric motors (not shown). Motors may be provided on the leading edge 21 or may be provided elsewhere on or near the awning apparatus 100 and attached to the leading edge 21 so as to cause the leading edge 21 to move with respect to the support structure 30. The storage roller 23 may be spring-loaded so as to provide a biasing force in the direction of retraction. This provides tension in the screen 20 when it is in a deployed state (and the leading edge 21 is held in an extended position) and provides a retraction force when the screen 20 is to be retracted (and the leading edge 21 is released). Alternatively, the storage roller 23 may be motor driven. Again, the storage roller 23 can be driven in the direction of retraction to create tension (if the leading edge 21 is held in place in an extended position) or can provide the retraction force to retract the screen 20 (if the leading edge 21 is released).

The first screen 10 and the second screen 20 can be extended and retracted separately, i.e. they may be separately driven and each have their own drive mechanism (e.g. separate motors). The first screen 10 and second screen 20 are however preferably controlled by the same control unit (which may be a remote control unit such as a hand-held controller) which can thus keep track of the two screens and their relative positions. The first screen 10 is made from a lighter weight material such as a mesh so as to provide some shade protection from the sun, but without being too heavy and with minimal obstruction of airflow so as to create a comfortable shaded area underneath the first screen 10. However, first screen 10 is not waterproof. Second screen 20 is waterproof and can be deployed if rain protection is also required. Second screen 20 is made from heavier fabric and thus obstructs airflow more than first screen 10. Each of screens 10 and 20 can be deployed to any suitable extension and held in place at that extension. Thus, if desired, the lighter first screen 10 can be deployed to a greater extent than the second screen 20. Thus rain protection can be provided for a smaller area than that provided for shade, simply by deploying first screen 10 to a greater extent than second screen 20.

Depending on the construction, it may be possible to extend either of the first screen 10 or the second screen 20 on its own. For example, if the side supports 33 are provided with two separate guide rails, one for the first screen 10 and one for the second screen 20, then it will be possible to extend either the first screen 10 on its own, the second screen 20 on its own or both the first and second screens 10, 20 together. With this construction it will also be possible to partially extend either or both screens 10, 20 to any selected position, so as to create different areas with different levels of protection. Alternatively, the side supports 33 may be provided with a single guide rail with both screens 10, 20 mounted in the same guide rail.

With this construction, the leading edge of one screen will be mounted in the guide rail forwardly of the leading edge of the other screen. For example, the leading edge 1 1 of the first screen 10 may be mounted forwardly (i.e. in the direction of extension towards the front supports 32) of the leading edge 21 of the second screen 20. With this arrangement, the second screen 20 cannot be extended to a greater extent than the first screen 10 as its leading edge 21 is constrained behind the leading edge 1 1 of the first screen and cannot overtake it.

The latter arrangement described above (with a single guide rail) is sufficient for many purposes, e.g. in the case of a lighter shade fabric with a heavier rain protection fabric, it is unlikely to be desired to extend the heavier rain protection fabric (i.e. second screen 20) when only sun protection (from first screen 10) is required. If the second screen 20 is to be deployed, it is necessary to deploy the first screen 10 to at least the same extent, but the functionality is uncompromised.

On the other hand, the former arrangement described above (with two separate guide rails) is more versatile. For example, two fabrics of different densities can be used to provide two different levels of shade with additive shading properties. If one screen (e.g. second screen 20) is heavier (or has a greater shading property) than the other screen (e.g. first screen 10), then three different levels of shading can be achieved: the lowest level of shade protection is provided by the first screen 10 alone (with the lower shading property), the second level of shade protection is provided by the second screen 20 alone (with the higher shading property) and the highest level of shade protection is provided by a combination of both the first screen 10 and second screen 20 being deployed together (with the additive shading properties combining together to produce a greater shading effect). Of course, as both screens 10, 20 are fully individually positionable in this arrangement, the awning can be arranged to provide two different levels of shading, the first level being from a single screen (either the first screen 10 for low shade protection or the second screen 20 for higher shade protection) and the second level being from the combined effect of both screens 10, 20 together.

The choice of screens 10, 20 can be selected from any available fabrics or materials according to the desired circumstances. For example, different colours of fabric can be used (or combined) to create different lighting effects.

Figure 2 shows a second embodiment of the invention. The second embodiment is the same as the first embodiment in all respects except that the first screen 10 is stored on a storage roller (not visible in the Figure) in the same may as the second screen 20. Thus the second embodiment has two storage rollers, one for each of the two screens 10, 20. The storage roller for the first screen 10 is located generally below the side supports 33 of the support structure 30, while the storage roller 23 for the second screen 20 is located generally above the side supports 33. However this arrangement is not essential and both storage rollers could be located above or below the side supports 33 if desired.

Figures 3, 4 and 5 show awnings with a flexible support structure rather than a rigid frame structure as shown in Figures 1 and 2. The flexible support structure uses longitudinal flexible elements 34 which may be wires, ropes, cables, straps or similar. The longitudinal flexible elements 34 extend from a first support 35 (e.g. a building facade in this embodiment) to second supports 36 (being support poles in this embodiment). The first screen 10 has a front bar 14 at its leading edge 1 1 . The second screen 20 has a front bar 24 at its leading edge 21 . The front bars 14, 24 provide the means by which the screens 10, 20 are mounted to the longitudinal flexible elements 34.

In Figure 3, the front bar 14 of the first screen 10 is mounted to the longitudinal flexible elements 34 forwardly of the front bar 24 of the second screen 20. Thus the second screen 20 cannot be extended further than the first screen 10, but can be deployed to any position of lesser extent than the first screen 10. Only a single set of longitudinal flexible elements 34 is required to support both screens 10, 20. In this embodiment, one longitudinal flexible element is provided at each side of the awning and both screens 10, 20 are attached to both longitudinal flexible elements 34. As in the first and second embodiments, the first screen 10 and the second screen 20 are independently movable so the first screen 10 can be extended without extending the second screen 20. The second screen 20 can be extended and retracted simultaneously with the first screen 10, or it can be extended separately from the first screen 10 at a later time. The second screen 20 must be retracted before the first screen 10 can be retracted.

In embodiments such as this where the two (or more) screens are mounted to the same support elements (rigid or flexible support elements), it is particularly important to have both screens controlled by the same controller as the potential movement of each screen can be limited by the current position of the other screen.

In this embodiment, both the first screen 10 and the second screen 20 hang down beneath the longitudinal flexible elements 34. Both the first and second screens 10, 20 are wider than the separation distance of the longitudinal flexible elements 34 and so when one or both of the screens 10, 20 is deployed, the longitudinal flexible elements 34 are obscured from view from beneath the screen(s).

The storage roller 13 of the first screen 10 is mounted on the support 35 at a lower position than the storage roller 23 of the second screen 20. Both storage rollers 13, 23 are mounted to the support 35 at a lower position than the mounting points of the longitudinal flexible elements 34. As the screens 10, 20 are maintained in tension during extension and retraction, this minimises contact between the two screens 10, 20 during extension and retraction and thus minimises friction and wear. To increase the separation between the screens 10, 20 at the leading edges, the leading edge 21 of second screen 20 may be mounted to the front bar 24 at a higher position on the front bar 24 than the mounting position of leading edge 1 1 of first screen 10 to front bar 14. This is illustrated in Figure 3A.

Figure 4 shows a fourth embodiment of the invention, being a variation of the third embodiment. The fourth embodiment is the same as the third embodiment except that the second screen 20 is disposed above the longitudinal flexible elements 34. The first screen 10 still hangs beneath the longitudinal flexible elements 34. Thus the longitudinal flexible elements 34 extend between the first screen 10 and the second screen 20. The front bars 14, 24 of the screens 10, 20 are still both mounted to both longitudinal flexible elements 34. As shown in Figure 4A, to improve the separation between the screens 10, 20 and the longitudinal flexible elements 34, the first screen 10 is mounted to the front bar 14 at a low position, while the second screen 20 is mounted to the front bar 24 at a high position. The storage roller 13 for the first screen 10 is mounted to the first support 35 below the longitudinal flexible elements 34 and the storage roller 23 for the second screen 20 is mounted to the first support 35 above the longitudinal flexible elements 34.

This arrangement allows better separation of the first screen 10 from the second screen 20 as the screens can be mounted to the respective front bars 14, 24 with a greater height differential than in the third embodiment, thus minimising the chances of contact between the screens 10, 20. Although the screens 10, 20 are maintained under tension during extension, retraction and while deployed, there is always some inevitable sagging of the screen fabric with an associated risk of contact between the screens, with associated friction and wear which is to be avoided.

Figure 5 shows a fifth embodiment of the invention. This embodiment is similar to the third and fourth embodiments, but differs therefrom in that each of the first screen 10 and the second screen 20 are provided with their own set of longitudinal flexible elements 34. The first screen 10 is mounted to first longitudinal flexible elements 34a (via front bar 14) and the second screen 20 is mounted to second longitudinal flexible elements 34b (via front bar 24). As shown in Figure 5, the first screen 10 hangs beneath the first longitudinal flexible elements 34a and the second screen 20 hangs beneath the second longitudinal flexible elements 34b, but is disposed above the first longitudinal flexible elements 34a.

Providing two separate sets of longitudinal flexible elements 34, one for each screen provides the same flexibility as described above in relation to the first and second embodiments where the rigid structure has separate guide rails for the two screens in the side support elements 33. In other words, either the first screen 10 or the second screen 20 can be deployed without the other. Or both first and second screens 10, 20 can be deployed together. Either screen 10, 20 can be deployed to a greater extent than the other, thus providing the maximum possible combinations of the properties of the two screens 10, 20. An additional benefit is that the longitudinal flexible elements 34a are separate from the longitudinal flexible elements 34b. Thus each screen 10, 20 is supported by its own longitudinal flexible elements 34 and the system therefore provides better redundancy. If one screen or one longitudinal flexible element fails, the other screen remains operational. Each longitudinal flexible element is also required to support less weight than in the third and fourth embodiments.

Although both the first screen 10 and the second screen 20 are shown hanging beneath their respective longitudinal flexible elements 34, in other embodiments, the screens 10, 20 could both be disposed above their respective longitudinal flexible elements or one could be disposed above while the other is disposed below. The particular arrangement that should be used can be selected by the skilled person according to the circumstances of the particular installation. In general, it is preferred to minimise the chances of contact between the first screen 10 and the second screen 20 as well as minimising the chances of contact between either screen 10, 20 and the longitudinal flexible elements 34. However, the possible mounting points of the longitudinal flexible elements 34 and the storage rollers 13, 23 for each installation have to be taken into account along with the aesthetics of the installation. In each of the third, fourth and fifth embodiments, the screens 10, 20 are each movable independently. The screens 10, 20 may be driven manually, but are preferably driven by electric motors provided in the respective front bars 14, 24. The motors drive rollers which are frictionally engaged with the longitudinal flexible elements such that as the rollers are turned, the front bar 14, 24 moves with respect to the longitudinal flexible elements 34. The front bars 14, 24 are also provided with a means for preventing rotation of the rollers. This could be done via engagement of the motor, via the gearing (e.g. a worm gear which cannot be driven in reverse) or via a separate braking system. By preventing the rollers from turning, the front bar 14, 24 is held in position relative to the longitudinal flexible element 34 by the frictional engagement between the roller(s) and the longitudinal flexible element 34. The mechanism is designed such that this engagement can withstand a large tension force applied to the screen 10, 20 in the direction of retraction, thus creating tension in the screen 10, 20 and keeping it taut throughout deployment. The storage rollers 13, 23 are also preferably electrically driven to pay out screen fabric during extension and to roll up screen fabric during retraction. The storage roller motor is also used to create and maintain tension in the screen during extension, deployment and retraction. All of the motors are controlled by a central control unit which monitors tension in the screens 10, 20 and synchronises the motors of each screen (i.e. the front motor(s) and the storage roller motor of each screen) so as to maintain tension in that screen.

Although the embodiments described above all have two screens, it will be appreciated that the concept can readily be implemented with more than two screens, for example, three, four or more screens could be used. Such

implementations may be useful in areas which are used for multiple different activities and where different screen types or materials may be needed for the different activities. In particular, the embodiments which use longitudinal flexible elements are particularly well suited to awnings with very large extensions (for example 10 meters or more) and can thus be used for example to cover sports areas where different lighting conditions or different weather protection may be required depending on the particular sports being played.