EP0956423B1 - Device for protection against the sun, of venetian blind type - Google Patents

Abstract

A Venetian type sunshade comprising a plurality of parallel lamellae with horizontally extending respective longitudinal axes, which are adapted to be rotated about their respective longitudinal axes using an adjusting mechanism. The lamellae, or a layer applied on the upper side of the lamellae, consists of a material transparent to sunlight. Each lamella has an upper side, a plurality of ribs, and a third face. Each rib has a first face arranged obliquely relative to the upper side of the lamella and adapted to be irradiated by the sun in an approximately vertical direction, and a second face which is arranged flush and at an acute angle of roughly 45° relative to the first flat element. The third face is approximately orthogonal to the second faces. Adjacent ribs define a mutual spacing which permits a low shade irradiation and emission through the first faces when there is approximately perpendicular irradiation of the first flat elements, with the optical connection between the mutual spacing being within the thickness between the upper side of a lamella and the third face.

Description

Technical field

The invention relates to a sun protection device in the manner of a blind with a large number of parallel slats with horizontal extending longitudinal axes and essentially flat, elongated Surface elements, each individual slat at such an angle from the The sun can be irradiated so that the horizontal view is largely retained.

State of the art

Sun protection devices of the aforementioned type, as they are known, for example, as louvre blinds made of vinyl or aluminum, only insufficiently fulfill the desire for a sun protection function that Protect you from direct glare from sunlight inside rooms should, on the other hand, a certain light transmission for the entry of Daylight allowed, so that artificial light is not used inside the room can. In addition, louvre blinds allow, especially when more complete Shading, no visual view through to the outside, but for the indoor climate as well as the living and working quality in such shaded areas Would be desirable.

In departure from the optically non-transparent materials for the use of Louver blinds are generic shading systems that are known make the fact that direct sunlight on buildings or window areas up to 80% of the incident light intensity from the solar and circumsolar solid angle. Mostly made of optically transparent Materials manufactured sun protection systems point directionally Transmission properties and especially hide the unwanted Angular ranges, preferably light from solar solid angles, from; are for the light components from other spatial directions are largely optically transparent. Examples of such a sun protection system are, for example, from US 631 220, US 3,255,665 and US 737,979 are known.

However, since the elevation angle of the sun changes continuously over the course of a year changes, such directional sun protection systems must either current position of the sun can be adjusted ("so-called active elements") or the Direction-selective properties are designed so that they are very constantly hide the large solid angle range of the sky ("so - called passive Elements").

An example of active elements is described in EP 0 090 830, from which one Sun protection device emerges in the form of slats translucent material is formed. The multitude parallel to each other arranged individual lamellae, each rotatable about their longitudinal lamella axis have a flat surface facing the sun, the opposite surface Surface with a prismatic structure, consisting preferably of parallel directed prism rods is provided. They are for effective sun protection individual surfaces facing the sun approximately perpendicular to each Align the incidence of light, so that the individual, made of optically transparent Light beams struck by material formed by total reflections be reflected back into the outside area. Although the well-known Sun protection device Daylight penetrate into the interior of the room, but is blocked due to the necessary orientation perpendicular to the sun considerable measure.

The so-called serves as a geometric indicator for louvre blinds Aspect ratio A / B, which is the ratio between the lamella spacing A between two adjacent blind slats and the slat width B indicates. In a diagram from this can be seen in FIG the percentage of that between the slat elements for a clear view prevailing area share depending on the settings of the Slat elements emerges, based on the changing during the day Elevation angle of the sun.

Those with the reference "View NormP." curve shows the area percentage, that between the prism lamellae according to that described above European publication as a review in a horizontal direction depending remains from the position of the sun. It can be seen that when the sun is high the individual slat elements must be aligned flat, which means that the free View between two adjacent slat elements is greater than in the case at positions with low elevation. In the curve "View NormP. "Is based on an aspect ratio A / B of 1.

Due to the requirement for vertical alignment of the individual slats the transparency properties are relative to the incident sun rays significantly affected. To address the disadvantages of essentially Lamellar structures are to avoid vertical alignment to the sun the light that strikes the slat surface obliquely blast off again. Such arrangements go from DE 44 42 870 A1 and DE 44 44 509 A1. The slats described therein for precise Control of direct solar radiation have one facing the sun sawtooth-like structure, but covered with a metal coating is. However, the disadvantage of these known sun protection systems is the strong one Heating of the metal surfaces, as they are between 5 and 15% depending on the version Flat sun protection devices with a lamellar structured surface go for example from the publications GB 2 220 025 A and GB 2 170 256 A as known. In both cases, it is sunlight-transparent Facade surfaces that are particularly suitable for greenhouses and that Sunlight at a desired angle of incidence into the interior of the Redirect the greenhouse. Admittedly occur with a suitable arrangement of the optically active surfaces of the sun protection devices on total reflections, but will the light, for example in the case of FIGS. 2 and 3 of GB 2 170 256 A, does not enter the reflected back in the same direction from which the light is directed towards the Sun protection device occurs. Dazzle effects in the environment are inevitable.

From US-A-4,773,733 a sun protection device (blind) is known, the has prism-shaped, reflective Venetian blind rods. The prismatic formation of the rods causes the impinging Sun rays are reflected at a certain angle. Are in practice however, adjustment deviations of the individual slats are unavoidable. The Solar radiation also has a certain angular difference. As a consequence, that radiation always passes the upper edge of the deflecting facet. This Radiation is only thrown back onto the deflecting facet if a dense one Conclusion is given. Otherwise this radiation will penetrate further, so that here too glare occurs in the room. The one proposed in US-A-4,773,733 Solution also offers the choice between a one-sided structure, that works with refraction, which can create colors, or one Execution structured on both sides, but which is more complicated to manufacture.

Presentation of the invention

The invention has for its object to provide a sun protection device according to Art a blind with a plurality of slats arranged parallel to each other horizontal longitudinal axes and essentially flat, elongated trained surface elements, with each individual slat under one An angle that can be irradiated by the sun is that the horizontal view is predominant is retained to develop in such a way that, on the one hand, the Transparent properties largely thanks to the sun protection device are unaffected or only slightly impaired and on the other hand any Prevents glare from direct sunlight on the interior of the room becomes. In particular, the sun protection device should not show any self-heating and be made of optically transparent material. After all, it applies Manufacture sun protection device cheaper.

The object on which the invention is based is achieved in claim 1 specified. Advantageous further developments are the subject of the subclaims.

Erste Flächenelemente, die schräg zur Lamellenoberseite angeordnet und von der Sonne ungefähr senkrecht bestrahlbar sind. Zweite Flächenelemente, die bündig und in spitzem Winkel von etwa 45° zu den ersten Flächenelementen angeordnet sind, und einem dritten Flächenelement, das in etwa senkrecht zu den zweiten Flächenelementen angeordnet ist. Insbesondere weisen benachbarte erste und zweite Flächenelementpaare einen Abstand zueinander auf, der bei einer ungefähr senkrechten Bestrahlung der ersten Elemente mit Sonnenlicht eine schattenarme Ein- und Abstrahlung des Sonnenlichtes über die ersten Elemente ermöglicht. Ferner sind über diesen Abstand entweder keine oder derartige optische Verbindungen vorgesehen, deren eine Oberfläche mit der Lamellenoberseite zusammenfällt und eine andere parallel zur dritten Fläche liegt oder mit dieser zusammenfällt. Schließlich kann direktes Sonnenlicht die Lamelle ausschließlich über die ersten Flächenelemente verlassen.

According to the invention, a sun protection device in the manner of a venetian blind with a plurality of parallel slats with horizontally extending longitudinal axes, which can be rotated about their longitudinal axes by means of an adjustment mechanism, is designed in such a way that the slats or a layer applied to the top of the slats consists of sunlight-transparent material , and has a cross section perpendicular to the longitudinal axis of the lamella, which is composed of the following surface elements:

First surface elements that are arranged at an angle to the top of the slats and can be irradiated approximately vertically by the sun. Second surface elements, which are arranged flush and at an acute angle of approximately 45 ° to the first surface elements, and a third surface element, which is arranged approximately perpendicular to the second surface elements. In particular, adjacent first and second surface element pairs are at a distance from one another which, when the first elements are irradiated approximately vertically with sunlight, enables a low-shadow irradiation and radiation of the sunlight via the first elements. Furthermore, either no or such optical connections are provided over this distance, one surface of which coincides with the top of the lamella and another lies parallel to or coincides with the third surface. After all, direct sunlight can only leave the slat via the first surface elements.

The alignment of the surfaces of the optical connectors parallel to the Third panel elements ensures that direct sunlight can hit the slat can only leave via the first surface elements. That aspect is important so that adjustment errors and other deviations from the ideal beam path Do not impair the function of the slat.

The invention is based on the idea that sunlight on the Slat top preferably strikes at an angle of about 40 ° -55 ° and is reflected back there by total reflection, preferably in the same Direction from which the sunlight falls on the sun protection device. To this Effective sun protection can predominantly be used with relatively small inclinations individual slats can be achieved around their longitudinal axes. As a result, the for horizontal viewing available free areas between the individual Slats become very large compared to blinds, which are usually normal, i.e. H. require vertical alignment of the slats to the sun. In the 2 give the lines "View 1", "View 0.9" and "View 0.8 "shows the freely visible areas that can be achieved with lamellas Reflective properties for sunlight that is below 45 ° on the slat surface strikes and is reflected back there as well as aspect ratios A / B of 1, 0.9 and 0.8. From the comparison of the line courses between the Lines "View 1", "View 0.9" and "View 0.8" with the line "View NormP", the indicates the visual part of the concept from EP 0 090 830 B1, it can be seen that a significant improvement in the visual properties of the new proposed concept is available.

Even in the proposed concept, the setting of the blind must match the current one Roughly follow the position of the sun to improve the sun protection effect and the horizontal view maximize at the same time. In case of deviations from an exact alignment everyone The following drop configurations are possible for individual blinds facing the sun:

Are the slats too flat oriented relative to the incoming sun rays, i. that is, this case can occur, in particular, when the sun is very low some of the light between the slats enters the room directly. This danger can be mitigated by changing the aspect ratio of every single slat element is reduced, i.e. either the Slat spacing reduced or the slat width increased. On Aspect ratio around 0.8, for example, ensures that the "uncovered" portion, i.e. the area with a clear view, for a low sun under 10% remains. This can be seen in particular in FIG. 2, in the lines with "uncovered 1", "uncovered 0.9" and "uncovered 0.8" sun positions with only low solar elevation are shown. Moreover, there would be a remaining one Cover gap between the individual slat elements none create significant overheating problems, especially with low Sun radiation already the intensity of the radiation through the long Atmospheric path is significantly weakened.

In the opposite case, if the individual slat elements are too steep, relative to the incoming sun rays, the sun protection effect would remain unaffected by this, but the horizontal view through the Slat arrangement unnecessarily greatly reduced.

In summary, it can therefore be stated that with small errors in the orientation of the lamella elements relative to the sunlight only minor losses in sun protection and in Horizontal viewing properties would be associated.

Brief description of the drawings

Fig. 1

Jalousieanordnung mit Verstellmechanismus,

Fig. 2

Diagrammdarstellung mit variablen Aspektverhältnissen,

Fig. 3

perspektivische Darstellung einer erfindungsgemäßen Lamellenoberflächenstruktur,

Fig. 4

Querschnittsdarstellung durch eine erfindungsgemäße Sägezahnstruktur,

Fig. 5

Ausführungsbeispiel gemäß Fig. 4 mit reflektierender Schicht,

Fig. 6a, b

Ausführungsform gemäß Fig. 4 mit zusätzlichen Reflexionsschichten.

Fig. 7

Jalousielamelle mit zusätzlicher Reflexionsschicht.

The invention is described below by way of example with reference to the drawing without limitation of the general inventive concept. Show it:

Fig. 1

Venetian blind arrangement with adjustment mechanism,

Fig. 2

Diagram representation with variable aspect ratios,

Fig. 3

perspective view of a lamella surface structure according to the invention,

Fig. 4

Cross-sectional representation through a sawtooth structure according to the invention,

Fig. 5

4 with reflecting layer,

6a, b

Embodiment according to FIG. 4 with additional reflection layers.

Fig. 7

Venetian blind slat with additional reflective layer.

The sun protection device shown in FIG. 1 has a drive mechanism M in its horizontal orientations adjustable slats L, each having a width B and a mutual distance A. In the example given, the lamella arrangement is mounted behind a window F in order to prevent the light rays coming directly from the sun from reaching the interior of the room. In order to improve the see-through property of the sun protection device, ie to maximize the freely visible areas of the area between the lamellae L, the surfaces of the lamellae are designed in such a way that sun rays striking the surfaces are preferably at an angle of 40 ° -55 ° relative to the surface plane in one Angle range α _{Refl be reflected} back. The lamella planes can be moved by means of the drive mechanism M about their respective longitudinal axes LA by an angle α _Lam . The sunlight striking the lamella surfaces (LO) is preferably reflected back in the same direction as it strikes the surface.

The front ones facing the solar radiation are preferably Slat edges on their underside with a reflective coating provided so that back-reflected light rays that are under a steeper Reflection angles are reflected back and in this way to the bottom the lamella above, on the reflective layer to the outside can be distracted.

As a suitable surface structure, either as a structured layer a transparent material as an additive to the surface of each slat is applied, for example as a transparent film, or the slat itself consists of the structure, basically serves a folded surface that Has surface sections that are substantially perpendicular to the incident Rays of light are oriented.

3 shows an embodiment of a lamella layer or shown as part of a complete slat. The one facing the sun Surface has parallel ribs R, the cross section of a Sawtooth structure correspond. The underside of the slat, however, is flat educated.

4 is a cross-sectional view through the inventive Surface structure of the lamella shown. Essential property of Surface structure is that an oblique to the top (LO) of the Slat-directed first surface EF, hereinafter also referred to as the reception surface, oriented largely normal to the sun by the slat as a whole is aligned accordingly to the sun. The essentially the Receiving surface EF perpendicularly penetrating sun rays meet one third surface HF running parallel to the lamella plane and are on this totally reflected. The totally reflected beam components then reach one second surface VF directed largely perpendicular to the upper side (LO) of the lamella and are totally reflected on this a second time, which leads to this Way deflected light rays essentially into the opposite Direction with which they hit the receiving surface EF. The deflected by the lamella structure shown in FIG. 4, respectively light rays reflected back essentially pass over the receiving surface EF back out into the open.

Due to the areal arrangement of the slats, it is made of geometric Reasons necessary, a large number arranged one behind the other in cross section in the Ribs essentially parallel to a sawtooth structure to be arranged, which in their entirety occupy the width B of the lamella L. Due to the height H of each individual structural element and their mutual spacing, preferably of the same order of magnitude H is supposed to cause problems of mutual shading in succession lying elements. One reason for this is the finite solid angle the sun and secondly the inevitable error in practice Alignment of the slats towards the sun. The reception areas EF adjacent Structural elements will either partially shade or it will Light striking between sections.

In principle, the angular range within which total reflection strikes depends on the refractive index of the optically transparent material of the layer applied to the lamella or the lamella itself. For polycarbonate with a refractive index n = 1.59, the angular aperture for total reflection is 9.6 °. α on ≤ n • (45 ° - α r ) = n • 45 ° - arcsin 1 / n = 9.6 °

The angle calculated above is referred to the normal Receiving area EF measured. To opt for possible losses within the To avoid transparent medium corresponds to the massive layer thickness D 4 ideally an integer multiple of the structure height H. If the dimensioning deviates from the ideal case, additional, actually unnecessary total reflections within the massive layer. In principle, the layer thickness D must also be reduced to zero, as a result of which Adjacent surfaces EF and VF are not visually connected to one another via connecting bridges are coupled. In this case, this is via the respective receiving area EF incident light again over this surface in the way of total reflection reflected back. The shading problems indicated above occur not in this case.

In Fig. 5, an embodiment is shown that between each one vertical surface VF and the corresponding adjacent one Receiving surface EF provides an additional reflecting surface RF. By this reflective surface RF prevents light from reaching a incidence angle deviating from the ideal case between two successive ones Receiving surfaces EF meets and also that too flat, back-reflecting light components on the respective back of the one in front Sawtooth element hits the vertical surface VF and in this way unwanted reflections and glare. Basically there are two Design variants for the realization of the reflecting surfaces RF possible: a solid design according to the embodiment according to FIGS. 6a and a mirrored version according to the embodiment of FIG. 6b.

The solid design according to FIG. 6a provides a coherent layer S covering the complete sawtooth structure, which consists of optically transparent material and has total reflection properties. Light falling steeply onto the lamella surface, which would fall between adjacent elements without an additional layer S, is now guided in a kind of light guide onto the receiving surface EF located at the rear. In return, light emitted by the receiving surface EF, which would run the risk of hitting the element in front because of its flat angle of reflection, is conducted via this element. An optical contact between the additional layer S and the reflective structure should not come about because then undesired reflections favor glare. The layer thickness of the additional layer S influences the angular tolerance within which the error possibilities described above can be eliminated. A sensible limit is the aperture of the element for total reflection, which corresponds to about 1 W. With the formula below d A = 2 • H • tan β / n = 0.16 H the recommended minimum thickness for the additional layer S should be 0.16EH.

As an alternative to a solid layer construction according to the embodiment according to FIG. 6a, the construction according to FIG. 6b provides a thin layer covering over the structural elements, in which the layer thickness d _A can be chosen to be as small as desired. Only the connection between a successive vertical layer and a receiving layer are to be covered with an reflecting layer.

As far as the individual slats are concerned, those described above Shading problems fixed using one of the above two options. For significant deviations of the slat alignment from the ideal alignment, especially if the slat is too flat to the sun, part of the reflected light hit the slat above. Precautions against it are possible by adding a reflective coating on the underside of the slat is applied, but no optical contact to the underside of the slats in order not to impair the total reflection properties.

The manufacture of the sun protection device according to the invention in the manner of a Venetian blind is fundamentally known with the means of profile production in the endless process, for example by means of extrusion processes or in One-off production using embossing processes made of transparent polymers. to Production of an entire lamella according to the exemplary embodiment according to FIG. 3 made of transparent material, for example polycarbonate, are known per se Extrusion and embossing processes known.

A second way of producing the invention Sun protection device consists of a film made of transparent material, For example, emboss polycarbonate and attach it to a slat. In 7 is a lamella L, curved for structural reasons, as a support structure shown on which the reflective by means of adhesive at the edge areas Film layer is attached as uncurved as possible. In the event that the film is elastic the blind can also be pulled up and stacked.

If, due to static considerations, the slat is slightly curved their axis is desired, the profile can be adjusted so that despite Curvature of the reflective layer optimal light deflection over the entire slat width is reached. For this, e.g. the vertical area VF in their alignment increasingly from the front to the rear edge of the slat tilted out of their vertical orientation.

The slats can preferably be made of transparent material, However, aluminum slats, for example, have the additional support Advantage that the underside of the slats automatically has reflective properties features.

Claims (6)

1. Sunshade device of the type of a Venetian blind comprising a plurality of lamellae (L) in parallel arrangement with horizontally extending longitudinal axes, which are adapted to be rotated about their longitudinal axes by means of an adjusting mechanism,
   characterised in that said lamellae (L) or a layer applied on the upper side of said lamellae (L) consists of a material transparent for sunlight, and has a cross-section orthogonal on the longitudinal axis of said lamellae, which is composed of

   (a) first flat elements (EF) arranged obliquely relative to the upper side (LO) of said lamellae and adapted to be irradiated by the sun in an approximately vertical direction;

   (b) second flat elements (VF) which are arranged flush and at an acute angle of roughly 45° relative to said first flat elements (EF) and

   (c) a third flat element (HF) arranged approximately orthogonally on said flat elements (VF);

   that adjacent pairs of (EF)-(VF) flat elements present a mutual spacing which permits a low-shade irradiation and emission via said first flat elements (EF) with an approximately vertical irradiation of said first flat elements (EF) with sunlight, and
   that via this spacing, i.e. the distance between adjacent pairs of (EF)-(VF) flat elements, either no or such optical connections are provided whose one surface is coincident with an upper side (LO) of a lamella whilst the other surface is parallel to said third surface (HF) or coincides therewith,
   such that direct sunlight can leave the lamella exclusively via said first flat elements.
2. Sunshade device according to Claim 1,
   characterised in that the spacing between the upper side (LO) of said lamellae and said third flat element (HF) presents a thickness being an integer multiple of the height H that corresponds to the structural height of said pairs of (EF)-(VF) flat elements above the upper side of said lamella (LO).
3. Sunshade device according to Claim 1 or 2,
   characterised in that said pairs of (EF)-(V) flat elements present straight or slightly curved flanks.
4. Sunshade device according to any of the Claims 1 to 3,
   characterised in that said inclined first flat elements (EF) of two respectively adjacent pairs of (EF)-(VF) flat elements are connected to a reflecting surface (RF).
5. Sunshade device according to any of the Claims 1 to 4,
   characterised in that a transparent layer can be applied onto the contour of said pairs of (EF)-(VF) flat elements, which bears directly on said inclined flat elements (EF) and interconnects said inclined first flat elements (EF) of two adjacent pairs of (EF)-(VF) flat elements.
6. Sunshade device according to any of the Claims 1 to 5,
   characterised in that a reflecting coating is applied on the underside of said lamellae, which does not have any optical contact with the underside.

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