Sunshade

Abstract

A sunshade in the form of an awning comprises a piece of flexible reflective material, suspended from a first elongate support and supported by a second elongate support. A force-exerting device, such

Description

Background to the Invention

[0001] This invention relates to a sunshade, for example an awning or parasol.

[0002] Cities, towns, buildings, and houses need to adapt to an increase in warming temperatures due to climate change. Increasingly, architects and designers are adapting to include ideas to mitigate radiant heat.

[0003] Cities especially experience the urban heat island (UHI) effect, which exacerbates the issue, and makes night time particularly uncomfortable as buildings and surrounding areas continue to experience higher temperatures because structures absorb heat during the day, and radiate it out during the night. This makes city life harder to endure, especially in the evening, when temperatures should be cooler, disturbing sleep for example. In the countryside, by contrast, with fewer buildings it is cooler at night, due to the lower urban heat island effect.

[0004] This means more people turn to air conditioning, and this further amplifies the issue. Firstly, internal heat from the building transferred to the exterior, further heating the city. Secondly, more power is used, meaning more CO2 is released. In addition, manufacturing of air conditioners which are increasingly in demand means more energy is needed to make the air conditioners and to transport and store them, etc.

[0005] Increasingly, processes and concepts for alleviating an increasingly hotter world and decreasing temperatures down are being adopted, but in a more holistic way. For example, governments and councils around the world have schemes to plant more trees, to increase shade.

[0006] Another concept is to paint roads and building roofs in light-coloured paint, to reflect sunlight. However, this is counterintuitive, especially in the winter, as the solar radiation is being reflected, when it should be absorbed to warm buildings and houses, to save energy when the weather turns cold. This idea is best suited to climates that do not have a harsh winter.

[0007] Awnings, gazebos, and parasols can be used, but are not always practical, especially in high winds. In other words, it is hazardous to leave them open to reflect sunlight when people are not at home.

[0008] Awnings in particular are not always practical and are not intended to be left unattended, due to exposure in high wind. Also, they must be durable, and therefore require expensive frames and mountings to be put up by an experienced person. It would also not be practical to have awnings in front of every window and would be costly.

[0009] Flags have an advantage in the wind, as the material is highly flexible and yields and flexes in high winds. The obvious disadvantage of a flag is that it will only cover the building if it is windy, and even then, the cover is minimal. With the material wavering in the wind temporarily, very little shade is given. Moreover, flags will only reflect the sunlight horizontally, which is a disadvantage to buildings caught in the reflection, as it does not help in reflecting the sunlight back into the sky, and into space.

[0010] Flags, if attached from the top, instead of at the side, also tend to wrap themselves up after being caught in the wind.

[0011] Reflective material would not work if it reflects the sunlight to another building or house, increasing its temperature rise, and adding to the UHI. Also, in the winter, such material will have to be taken down, adding to the cost.

[0012] Sunlight needs to be reflected into the sky so that the heat does not stay at ground level, but is dissipated into the sky, away from built up areas, before they absorb the heat. Summary of the Invention

[0013] It is an aim of the invention to provide a sunshade that alleviates at least some of the abovementioned disadvantages.

[0014] Accordingly, a first aspect of the invention provides a sunshade in the form of an awning, comprising a piece of flexible reflective material, suspended from a first elongate support, and supported by a second elongate support, and a forceexerting device attached at least indirectly to the flexible material at a location remote from the first elongate support, such that when the flexible material is displaced by wind, the force-exerting device is arranged to return the flexible material to the at-rest position.

[0015] The force-exerting device can comprise a weight or a motor.

[0016] The second elongate support may include a gap through which extends the flexible material, or a flexible elongate element, such as a string, rope, chain, wire or cable, attached to the flexible material and to the force-exerting device. Where the force-exerting device comprises a weight, the weight may be wider than the gap, to prevent passage of the weight through the gap.

[0017] Where the force-exerting device comprises a weight, a platform can be provided for supporting the weight in the at-rest position, the height of the platform being variable to vary an angle at which the flexible material is disposed.

[0018] The flexible elongate element may extend through a tube.

[0019] The first elongate support may comprise a roller around which the flexible web can be rolled.

[0020] The first and / or second elongate supports may be elements of a frame.

[0021] An angle and / or a distance between the first and second supports may be variable to adjust a position of the flexible material.

[0022] A second aspect of the invention provides a solar panel assembly comprising a solar panel and a sunshade as described above, such that in a first position of the sun, the solar panel is arranged to receive sunlight directly, and in a second position of the sun, the solar panel is arranged to receive sunlight reflected by the awning. "Solar panel" as used herein includes a solar water heater as well as a photovoltaic panel or a solar concentrator.

[0023] A third aspect of the invention provides a method of directing solar energy, comprising providing a sunshade as described above and adjusting the height and / or azimuth of at least one of the supports, at different times of day and / or different times of year. Brief Description of the Drawings

[0024] Embodiments of the invention will now be described in more detail, by way of example only, with reference to the accompanying drawings, in which:

[0025] Figure 1 is a front view of an awning according to the invention;

[0026] Figure 2 is a side view of the awning of Figure 1;

[0027] Figure 3 is a front view of an alternative awning according to the invention;

[0028] Figure 4 is a side view of the awning of Figure 3;

[0029] Figure 5 shows an awning having a motorised force-exerting device;

[0030] Figure 6 shows an awning comprising a platform for a weight of the awning;

[0031] Figure 7 shows a solar panel assembly according to the invention;

[0032] Figure8 is a front view of another alternative awning;

[0033] Figure 9 is a plan view of supports for an alternative awning according to the invention; and

[0034] Figure 10 is a plan view of the supports of Figure 9 in a different configuration. Detailed Description of Particular Embodiments

[0035] Figures 1 and 2 show an awning in an at-rest position. The awning comprises a piece of flexible material 2, attached at one end to, and suspended from, an elongate horizontal support 4.

[0036] The material 2 is draped over a second elongate horizontal support 6 which is below, and spaced horizontally from, the first support 4.

[0037] A weight 8 is attached to a free edge of the material 2 by means of a string 10.

[0038] If the wind blows the flexible material 2 upwards, off the second support 6, the weight 8 returns it to the position shown in Figures 1 and 2.

[0039] Figures 3 and 4 show an alternative awning. In this embodiment, the second horizontal elongate support 26 includes a slot 28 through which the flexible material 2 extends. The weight 8 is too wide to pass through the slot 28. This limits the extent of movement of the flexible material 2.

[0040] Figure 5 shows an awning in which a motorised winch 30 is attached to the flexible material 2. The winch 30 fulfils the same purpose as the weight 8 in Figures 1 and 2. In still a further embodiment (not shown), a spring or bungee can be arranged to return the flexible material to the at-rest position.

[0041] Figure 6 shows an awning which is the same as that of Figures 1 and 2 except that the weight 38 rests on a platform 40. The height of the platform is adjustable. In this way, the position of the lower edge of the flexible material, and the angle at which the flexible material is disposed, are adjustable.

[0042] Figure 7 shows an assembly comprising an awning of the type shown in Figures 1 and 2, and a solar panel 50 mounted on a roof 52. At a first time of day, the sun is at a position to the right hand side as viewed, and irradiates the solar panel 50 directly. At a second time of day, the sun is at a position "out of the paper". In this position, the solar radiation strikes the flexible material 2 and is reflected thereby to the solar panel 50.

[0043] In each of the embodiments of Figures 1 to 7, the first support 4 can optionally be a roller which can be operated to roll the awning up. The first and second supports may be elements of a frame for the awning.

[0044] In a “flagpole" embodiment of the invention, the support for the flexible material is in the form of a single horizontal bar extending from a vertical pole. The horizontal bar can be rotatable to different azimuths, either rotating around the vertical pole, or by the pole rotating. Again this means the reflective material can be varied to reflect solar energy away from a window or door, in summer, and into the window or door, in winter, or onto a solar panel.

[0045] Figure 8 shows an awning in which the string 10 extends through a tube 60. This provides greater safety and control. The weight 8 may be small enough to pass through the tube, as shown, or may be too large to pass through. As a further alternative the weight could be capable of passing up the tube but be prevented from exiting by a small aperture at the top of the tube.

[0046] Figure 9 is a plan view of alternative supports for an awning. A first support 104 extends from a vertical pole 80. A second support 106 extends from the pole 80 below the first support 104. The second support is on an angled arm in order to be disposed parallel to and spaced horizontally from the first support 104. A piece of flexible material (not shown in Figure 9) is supported in the manner described with reference to Figures 1 and 2.

[0047] The horizontal supports 104,106 can be rotatable to different azimuths. This can, for example, be achieved by fixing both supports to the vertical pole 80, which is rotatable about its own axis.

[0048] In the embodiment of Figure 10, the second support 106 can rotate about the pole 80, to be disposed at an angle to the first support 104.

[0049] Where the support, or one or both supports, is / are rotatable, the position of the reflective material can be varied to reflect solar energy away from a window or door, in summer, and in through the window or doorway, in winter, or onto a solar panel.

[0050] In all cases, the vertical pole or its base can be telescopic to vary its height.

[0051] It is also possible for one of the supports to move translationally with respect to the other support, for example by means of a hydraulic mechanism. Such movement may be vertical and / or horizontal.

[0052] The drawings show supports in the form of straight horizontal bars, but alternative supports are possible. One possible support is in the form of a curved bar. Another possible support takes the form of at least one flexible string, rope, cable or chain, for example two strings, fixed to the flexible material at upper corner regions thereof.

Claims

1. A sunshade in the form of an awning, comprising a piece of flexible reflective material, suspended from a first elongate support, and supported by a second elongate support, and a force-exerting device attached at least indirectly to the flexible material at a location remote from the first elongate support, such that when the flexible material is displaced by wind, the force-exerting device is arranged to return the flexible material to the at-rest position.

2. A sunshade according to claim 1, wherein the force-exerting device comprises a weight.

3. A sunshade according to claim 1, wherein the force-exerting device comprises a motor.

4. A sunshade according to claim 1, 2 or 3, wherein the first elongate support comprises a substantially horizontal bar.

5. A sunshade according to claim 4, wherein the first elongate support is rotatable to different azimuths.

6. A sunshade according to any preceding claim, wherein the second elongate support includes a gap through which extends the flexible material.

7. A sunshade according to any one of claims 1 to 5, wherein the second elongate support includes a gap through which extends a flexible elongate element attached to the flexible material and to the force-exerting device.

8. A sunshade according to claim 6 or 7, wherein the force-exerting device comprises a weight and the weight is wider than the gap.

9. A sunshade according to any preceding claim, wherein the force-exerting device comprises a weight attached to a flexible elongate element or the flexible elongate element, the flexible elongate element extending through a tube.

10. A sunshade according to any preceding claim, wherein the force-exerting device comprises a weight, and a platform is provided for supporting the weightin the at-rest position, the height of the platform being variable to vary an angle at which the flexible material is disposed.

11. A sunshade according to any preceding claim, wherein the first elongate support comprises a roller around which the flexible material can be rolled.

12. A sunshade according to any preceding claim, wherein the first and / or second elongate supports are elements of a frame.

13. A sunshade according to any preceding claim, wherein the second support is rotatable to different azimuths.

14. A sunshade according to any preceding claim, wherein an angle between the first and second supports is variable, to adjust a position of the flexible material.

15. A sunshade according to any preceding claim, wherein a distance between the first and second supports is variable, to adjust a position of the flexible material.

16. A solar panel assembly comprising a solar panel and a sunshade according to any preceding claim, such that in a first position of the sun, the solar panel is arranged to receive sunlight directly, and in a second position of the sun, the solar panel is arranged to receive sunlight reflected by the flexible material.

17. A method of directing solar energy, comprising providing a sunshade according to any one of claims 1 to 15 and adjusting the height and / or azimuth of at least one of the supports, at different times of day or different times of year.

Images