Field of application
[0001] In its most general aspect the present invention regards a solar radiation screening
system having an improved structure and capable of being applied near windows of a
building as well as comprising a plurality of movable sun louver elements supported
in a parallel relation with a predetermined interval along horizontal axes and at
a predetermined distance from said windows.
[0002] More particularly, the invention regards a movable sun louver element incorporated
in the abovementioned screening system.
[0003] The invention substantially regards the field of "daylighting", i.e. the techniques
that provide for maximum exploitation of natural light limiting the use of artificial
light for daylighting public or residential buildings and the description that follows
is provided with reference to this field of application with the sole aim of simplifying
exposure thereof.
Prior art
[0004] As well known, in this specific technical field, natural lighting has beneficial
effect on human health and it simultaneously allows reducing the use of artificial
lighting, with the ensuing consequences in terms of consumption of electrical energy.
[0005] Over the last years, there has been an ever-growing need for reducing energy consumption
and this has given rise to the so-called "daylighting" techniques which provide for
maximum exploitation of natural light limiting the use of the artificial one. This
leads to advantageous effects even in terms of lower costs required for heating or
cooling a building to which such techniques are applied.
[0006] A correct application of the "daylighting" techniques however starts from the assumption
that there suitably arises the need for direct solar radiation screening of the window
surfaces of the buildings, whether simple windows or entire glass facades.
[0007] This allows regulating the amount and quality of daylight penetrating into the rooms
of a building through the glass surfaces thereof.
[0008] This regulation, though desirable for all types of public or private buildings, would
be particularly suitable especially in case of high buildings provided with entire
glass facades.
[0009] Various solutions for solar radiation screening for these types of buildings are
already known; for example, different types of fixed or movable sun louvers to be
mounted near the windows are known.
[0010] There are various types of fixed sun louvers: they may be made up of a simple projection
extended cantilevered above the glass surface or a plurality elements arranged in
a parallel relation with a regular interval. In the latter case, the sun louvers are
made with laminar sections, preferably wing-shaped, which are mounted horizontally
at a predetermined distance from the glass surface. The number and spacing thereof
are defined according to the application needs, depending on whether maximizing the
screening effect or maximizing the external vision of the occupants of the building
is required.
[0011] Though guaranteeing the passage of air and light, these sun louvers have the great
disadvantage of being fixed and irremovable and not capable of efficiently regulating
the solar radiation according to the variation of the hours of the day.
[0012] Sun louvers of the movable type which have become more and more common in public
environments that are mainly used during the day such as hospitals, schools, offices,
commercial and industrial buildings are also known.
[0013] These movable sun louvers are relatively complex structures in which a plurality
of orientable blades are supported in a parallel relation on respective axes held
by a metal frame structure. These blades rotate cohesively each around the support
axis thereof and the most sophisticated systems are provided with a system for controlling
the movement based on environmental sensors and connected to mechanisms actuated by
electric or hydraulic cylinder gear motors. The rotation of the blades is regulated
according to the environmental conditions, i.e. solar radiation, the force of the
wind or presence of clouds. Regulation may also occur according to functions programmed
through a time calendar.
[0014] Though advantageous from various points of view, and substantially meeting the purpose,
these movable sun louvers systems are extremely complex and expensive and they do
not always guarantee ideal visibility within the buildings on which they are installed.
[0015] Furthermore, the movement of the sun louver solely allows regulating the inclination
thereof with respect to a vertical axis, but it does not allow performing other types
of movements which could have an impact on the surface exposed to the incident solar
radiation. Thus, this implies that several sun louver elements arranged in a parallel
relation with a small interval to achieve the object of an efficient screening, are
required. Alternatively, the use of a lesser number of sun louvers but having a considerable
dimension with respective installation and management costs could be provided for.
[0016] The technical problem on which the present invention is based is that of providing
a new solar radiation screening system by means of movable sun louvers having structural
and functional characteristics such to allow regulating the amount and quality of
light upon the variation of the hours of the day but reducing the number of sun louver
elements required for the purpose, thus overcoming the drawbacks of the solutions
currently proposed by the prior art.
[0017] Another object of the present invention is that of providing a solar radiation screening
system that is compatible with the architecture, and in particular with the facade,
of the building for which it is intended.
[0018] A further object of the invention is that of providing a solar radiation screening
system capable of always conferring a different aspect to the building on which it
is installed as the hours of the day progress.
Summary of the invention
[0019] The solution idea on which the present invention is based is that of providing movable
sun louvers having blades mounted on rotating axes which allow inclination thereof
with respect to a horizontal plane but which can be extended width-wise from a minimum
width to a maximum width. Thus, each sun louver is capable of telescopically increasing
the screening surface.
[0020] Advantageously, the abovementioned blades are also partly traversed by the incident
light radiation.
[0021] According to this solution idea, the technical drawback is overcome by a system of
the previously indicated type and characterised in that at least one of said sun louver
elements comprise a pair of blades parallel to each other and slidably mounted one
on the other so as to achieve a greater or lesser extension of the exposed surface
of the sun louver.
[0022] Advantageously, the sun louver elements comprise blades partly traversed by the incident
light radiation.
[0023] Furthermore, the blades are obtained by means of a close-mesh grating or by means
of a thick netting or even by means of a perforated plate.
[0024] The invention also regards a sun louver element for solar radiation screening systems
and of the type intended to be mounted with other elements of the same type near windows
of a building and rotatably supported on a horizontal axis parallel to the other elements
and at a predetermined distance from said windows, characterised in that it comprises
a pair of blades parallel to each other and slidably mounted one on the other so as
to achieve a greater or lesser extension of the exposed surface of the sun louver.
[0025] Further characteristics and advantages of the system and of the sun louver according
to the present invention shall be clear from the description, provided hereinafter,
of a preferred embodiment provided by way of non-limiting example with reference to
the attached drawings.
Brief description of the drawings
[0026]
- figure 1 represents a perspective and schematic view of a building provided with a
solar radiation screening system obtained according to the present invention;
- figure 2 shows a perspective and schematic view of a movable sun louver element incorporated
in the screening system of figure 1;
- figure 2 A shows a perspective view of the sun louver element of figure 2 at an operative
condition;
- figure 3 shows a side schematic view of the movable sun louver element of figure 2
in two different operative conditions;
- figure 4 shows a perspective view - with parts detached - of a detail of the sun louver
element of figure 2;
- figure 5 shows a perspective view of the assembly of the parts illustrated in figure
4 assembled together;
- figures 6 and 7 are perspective and schematic views of a screening system according
to the invention in two different operative conditions;
- figures 8 and 9 are vertical cross-section schematic views of a portion of the building
of figure 1 provided with the system of the present invention and in two different
operative conditions corresponding to two different hours of the day.
Detailed description
[0027] With reference to the attached figures, a solar radiation screening system 1 provided
according to the present invention is indicated in its entirety with 1.
[0028] The system 1 is capable of being applied outside near windows 4 of a building 2 and
comprises a plurality of movable sun louver elements 3 supported in a parallel relation
along horizontal axes in predetermined relation spaced from each other and from said
windows 4.
[0029] The system 1 is particularly indicated for tall and lean buildings such as flats
or skyscrapers with facades 5 almost entirely enclosed by perimeter windows 4. However,
the invention can also be applied on public and/or residential buildings of any type
or size, even pre-existing ones provided with normal windows.
[0030] In the example provided herein by way of non-limiting example with reference to figure
1, the building 2 is a cylindrical or a polygonal base tower with a high number of
sides, for example an octagon or a dodecagon, and comprises perimeter facades 5 enclosed
by large windows 4 extended from the floor to the ceiling of each floor as shown for
example in the section of figure 8.
[0031] Each movable element 3 incorporated in the system 1 is structured with a pair of
elongated rectangular-shaped blades or panels 6, 7, i.e. blades or panels in which
the longitudinal extension is considerably greater than the lateral one, for example
by a ratio of at least 4:1, or greater.
[0032] Advantageously, the blades 6, 7 lie on planes parallel to each other and they are
slidably mounted one on the other.
[0033] A sliding device 10, to be described in detail hereinafter, for adjusting the mutual
moving away or approaching of the blades 6, 7, still with parallel planes, so as to
achieve a greater or lesser extension of the exposed surface 8 of the sun louver 3
is provided for. Due to this solution, the surface 8 of the sun louver 3 exposed to
the incident light radiation varies in a substantially telescopic manner.
[0034] Advantageously, according to the present invention, the blades 6, 7 are not entirely
opaque or, in other words, they are partly traversed by the incident light radiation.
[0035] More in particular, each blade is made by using a close-mesh grating or a thick netting.
Alternatively, the blades 6, 7 may be obtained by means of a perforated plate, i.e.
a plate provided with a plurality of small through holes distributed regularly. This
solution allows reducing heat radiation and allows a greater amount of light energy.
[0036] A man skilled in the art can observe that any alternative embodiment may serve the
purpose, such as for example an open-mesh fabric.
[0037] The components of the sun louver 3 are preferably made of metal material; however,
other materials can be used for the blades 6, 7 or for parts of the sliding device
10.
[0038] In a preferred embodiment, each blade 6, 7 has a plate-like longitudinal edge 11,
12 extended perpendicularly to the laying plane of the respective blade 6, 7 and which
confers a drawer-like configuration to each one of them.
[0039] Various transverse stiffening ribs 9 which are regularly distributed on the surface
8 and extended from one longitudinal edge to the other are also provided for.
[0040] When the sun louver element 3 is in the position of minimum extension with the blades
6, 7 overlapped with respect to each other, the resulting overall configuration is
box-shaped, as shown for example in figure 2 A.
[0041] It should also be observed that the particular perforated structure of the blades
6, 7 makes the sun louver 3 capable of providing a screening filter having greater
or lesser intensity depending on the overlapping percentage of the blades. Therefore,
in the configuration of figure 2 A, in which the blades 6, 7 are completely overlapped,
and which shall be referred to as "closed", allows obtaining an almost complete screening
with considerable reduction of the lighting radiation passing through the sun louver.
[0042] In the other intermediate or "open" configurations, in which the blades 6, 7 are
partly overlapped on each other, a mixed filtering effect with two longitudinal end
strips partly traversed by the lighting radiation and a central strip which divides
them wherein the filtering effect is greater due to the overlapping of the blades
6, 7 is obtained. This effect can be observed in the example of figure 6.
[0043] It should be observed that when the blades 6, 7 are in the configuration of maximum
extension the width thereof substantially corresponds to the interval between the
sun louvers 3.
[0044] All this has an impact not only in terms of the screening capacity of the system
1 according to the invention, but also in terms of the perception of the screening
system by an observer outside the building 2 on which the system 1 is installed.
[0045] Actually, the building 2 is perceived differently depending on the relative position
of the two blades of each sun louver and the arrangement thereof varies depending
on the hours of the day and depending on the facades of the building, more or less
hit by the incident light radiation. Thus, the building 2 in its entirety appears
to an external observer always differently as the hours of the day progress, or upon
variation of the climatic conditions which have an impact on the light radiation.
[0046] With reference to the example of figure 4, following is a detailed description of
the sliding device 10 of the blades 6, 7 comprising slides 14, 18 integral with the
respective blades 6, 7 and slidably mounted on a guide or rail 13.
[0047] The slides 14, 18 are C-shaped.
[0048] The rail 13 is formed by a pair of S-shaped sections 19, 19' and made integral with
each other arranged facing each other in predetermined relation spaced so that there
is a substantially T-shaped interstice 16 therebetween.
[0049] A respective slide 14 or 18 is integral with a corresponding smaller side of the
blades 6, 7.
[0050] More in particular, with reference to the position of the blades 6, 7 illustrated
in figure 2, guides 14 each associated to the opposite smaller sides of the blade
16 can be identified as upper guides, while the guides 18 associated to the opposite
smaller sides of the blade 7 can be identified as lower guides.
[0051] The upper guides 14 are received in the upper part of the interstice 16 of the rail
13, substantially in the head part of the T-shaped interstice 16.
[0052] The lower guides instead slide outside the rail 13 surrounding the lower and narrower
portion of the rail.
[0053] Wheels 20 for facilitating sliding are provided for inside the guides 14, 18.
[0054] A gear wheel 15 part of a rack gear is advantageously housed, internally and centrally
with respect to the rail 13, in the interstice 16.
[0055] A tooth 21 conjugated to the wheel 15 of the rack gear is provided at the bottom
of each guide 14, 18. The wheel 15 is integral with a sleeve or hub 23 projecting
laterally and from opposite parts of the sun louver 3.
[0056] A rotation of the wheel 15 causes an equal and opposite kinematic action on the upper
slides 14 and on the lower slides 18 which are actuated mutually moving away and approaching
each other obtaining a translation of the respective blades 6, 7 in the direction
of the arrow F of figure 3.
[0057] Motorised means for driving the angular excursion of the gear wheel 15 by rotatingly
actuating the hub 23 integral therewith are provided. Such means are not represented
in the drawing in that they are of the conventional type and they can be provided
as an electric step motor mounted on board the sun louver 3 or housed laterally with
respect thereto in a recess of the perimeter upright 24 of the building 2.
[0058] Further motorised means for adjusting the inclination of the sun louvers 3 with respect
to a vertical axis are also provided.
[0059] Such further motorised means provide for an electric step motor which actuates a
shaft 25 connected to output and control signals coming from an electronic device
in which data and information regarding the ideal inclination according to the latitude
and depending on the hour of the day of a given season of the year are memorised.
[0060] The shaft 25 traverses the hub 23 and it further passes with limited clearance through
a hole 27 obtained centrally in the gear wheel 15.
[0061] The end of the shaft 25 is centrally made integral with the rail 13 so that a rotation
of the shaft 25 causes a direct and corresponding angular excursion of the rail 13,
and of the entire sun louver 3, with respect to vertical axis.
[0062] The shaft 25 essentially coincides with the axis for supporting the sun louver 3
which can thus be oriented around such axis.
[0063] Should the rotational movement of the sun louver 3 around the axis thereof require
to be kept independent from the translation movement and mutual sliding of the blades
6, 7, then there arises the need of maintaining clearance between the shaft 25 and
the hub 23 of the rotatable support.
[0064] On the contrary, should a simpler screening structure be sufficient, depending on
the application needs, then the shaft 25 and the hub 23 can be made integral so that
the rotation of the first causes an analogous rotation of the gear wheel 15 and a
corresponding relative sliding of a blade 6 on the other blade 7.
[0065] The examples of figures 8 and 9 show in a section on a vertical plane how the interior
spaces inside the building 2 appear near the perimeter windows provided with the screening
system of the present invention.
[0066] An operative condition in which the solar radiation is minimum and the sun louvers
3 are extended in a parallel relation on a horizontal plane or with an inclination
of only 10°, with the blades 6, 7 in closed position, is illustrated schematically
in figure 8. This situation minimises the screening and maximises the amount of light
which penetrates into the building.
[0067] An operative condition which occurs when the sun is on the southern side of the building
2 at about 70° on the zenith is illustrated in figure 9 instead; the sun louvers 3
are inclined in such a manner to be substantially perpendicular to the incident light
radiation offering the maximum screening possible to the windows 4 of the building
2, with the blades 6, 7 totally open.
[0068] It can be observed how in this case the visibility towards outside is guaranteed
in any case.
[0069] To complete the description, it should be pointed out that the screening system of
the present invention can be installed by providing aligned units of sun louvers 3,
as shown in figures 6 and 7.
[0070] The overall movement of the sun louvers 3 can be achieved by connecting the driving
shafts 25 to each other by means of interconnection joints.
[0071] There is also the possibility of connecting the shafts 25 by means of constant velocity
joints which allow connecting the sun louvers to each other according to a broken
line to achieve a slightly curvilinear configuration which can also be applied on
curved glass surfaces.
[0072] The various components of the system 1 or of the sun louver 3 can be made using different
types of materials; for example metal materials such as aluminium or zinc-plated or
painted steel or, more economically, synthetic plastic material such as PVC, which
has the advantage of preventing overheating due to solar radiation.
[0073] The invention overcomes the technical drawback and achieves various advantages the
first of which definitely lies in the fact that the screening system of the present
invention requires a lesser number of sun louver elements with respect to the prior
art solutions given that the slidable double blades of each sun louver can substantially
double the extension of the exposed surface of the sun louver during the operative
step.
[0074] Further advantages lie in the fact that the system of the present invention becomes
an important component of the overall aesthetic properties of the building which,
as previously indicated, can assume a different aspect from one facade to the other
to an external observer.
[0075] The man skilled in the art shall observe how the system of the present invention
can be subjected to modifications and variants all falling within the scope of the
invention.
[0076] For example, photovoltaic cells for generating electric energy sufficient for moving
the screening system can be housed in the sun louver 3.
[0077] Furthermore, the shape and the profiles of the blades of the sun louvers can be selected
according to their aesthetic properties or according to their capacity to support
the action exerted by the wind.
[0078] The movement of the sun louver elements allows calibrating the orientation according
to the current external conditions. This allows optimising the entry of the solar
radiation so as to intercept the high rays of the summer sun but allow the penetration
of the low winter radiation.
[0079] Lastly, the system of the present invention facilitates the regulation of the microclimate
inside the building, improving the heat comfort of the occupants thereof.
1. Solar radiation screening system (1) with movable sun louvers (3), of the type capable
of being applied at windows (4) of a building (2) and comprising a plurality of said
movable sun louver elements (3) supported in a parallel relation with a predetermined
interval along horizontal axes and at a predetermined distance from said windows (4),
characterised in that at least one of said sun louver elements comprises a pair of blades (6, 7) parallel
to each other and slidably mounted one (6) on the other (7) so as to achieve a greater
or lesser extension of the exposed surface (8) of the sun louver.
2. Screening system according to claim 1, characterised in that said sun louver elements (3) comprise blades (6, 7) partly traversed by the incident
light radiation.
3. Screening system according to claim 2, characterised in that said blades (6, 7) are obtained by means of a close-mesh grating or by means of a
thick netting or even by means of a perforated plate.
4. Screening system according to claim 1, characterised in that each blade (6, 7) is mounted on corresponding slides (14, 18) slidable on a rail
(13) integral with the respective support axis of the sun louver (3), gearing means
(15, 21) being provided for adjusting the mutual sliding of the slides (14, 18) and
of the corresponding blades (6, 7).
5. Screening system according to claim 1, characterised in that the maximum extension of the blades (6, 7) corresponds to the interval between the
sun louvers (3).
6. Screening system according to claim 4, characterised in that it comprises motorised means for independently rotating the sun louver about the
horizontal axis and rotating said gearing means.
7. Screening system according to claim 4, characterised in that it comprises a motor shaft (25) integral with said rail (13) and coaxial with said
support axis; multiple units of sun louver elements (3) being connected aligned with
respect to each other by means of interconnection joints of the motor shafts.
8. Sun louver element (3) for solar radiation screening systems and of the type intended
to be mounted with other elements (3) of the same type at windows (4) of a building
(2) and rotatably supported on a horizontal axis parallel to the other elements (3)
and at a predetermined distance from said windows (4), characterised in that it comprises a pair of blades (6, 7) parallel to each other and slidably mounted
one (6) on the other (7) so as to achieve a greater or lesser extension of the exposed
surface (8) of the sun louver.
9. Sun louver element according to claim 8, characterised in that said blades (6, 7) are obtained by means of a close-mesh grating or by means of a
thick netting or even by means of a perforated plate.
10. Sun louver element according to claim 8, characterised in that each blade (6, 7) is mounted on corresponding slides (14, 18) slidable on a rail
(13) integral with the respective axis for supporting the sun louver (3), gearing
means (15, 21) being provided for adjusting the mutual sliding of the slides (14,
18) and of the corresponding blades (6, 7).