EP4077864B1

EP4077864B1 - A roller screen, in particular an insect net

Info

Publication number: EP4077864B1
Application number: EP20828519.7A
Authority: EP
Inventors: Martin Birkkjaer; Per Solsø HINDHEDE
Original assignee: VKR Holding AS
Current assignee: VKR Holding AS
Priority date: 2019-12-20
Filing date: 2020-12-17
Publication date: 2023-10-04
Anticipated expiration: 2040-12-17
Also published as: EP4077864C0; HUE064228T2; WO2021121514A1; EP4077864A1

Description

Technical Field

The invention relates to a roller screen, in particular in the form of an insect net or the like, for shielding a building aperture, in particular a roof window area, in an inclined wall, which roller screen comprises: a top casing defining a first longitudinal direction and in which a spring-biased roller bar is arranged rotatably, a bottom bar configured to extend substantially in parallel with the top casing and being manually operable, a first side rail and a second side rail, each extending in a second longitudinal direction, substantially perpendicular from a respective end of the top casing and comprising at least a first track with an opening and delimited by a front flange, a leg, a protruding flange and an upstanding flange portion, the openings of the first side rail and the second side rail facing one another, and a screening body having two side edges and a predefined length between a first end portion connected to the roller bar and a second end portion connected to the bottom bar, said screening body being movable in the second longitudinal direction between a non-screening position and a screening position in which the screening body is unwound from the roller bar and covers the building aperture, the two side edges of the screening body being provided with discrete or continuously positioned thickenings guided in the first track and having a transverse dimension larger than the opening.

Background Art

A well-known challenge in relation to screening devices of the above mentioned type is to achieve hassle-free operation of the movable parts of the screening device. One obstacle that may arise during operation relates to the movement of the screening body in the second longitudinal direction by pulling/pushing the bottom bar. In order to ensure proper operation, it is vital to keep the bottom bar as parallel as possible to the top casing, i.e. the first longitudinal direction, in order to prevent snagging or catching of the ends of the bottom bar as they move along the side rails. One solution to this problem is the introduction of a parallel guidance cord system in which cords are typically first guided from one corner of the screening device along one side rail, along the bottom bar and finally along the other side rail up to the diagonally opposite corner of the screening device to provide a substantially H-shaped configuration of the cord system. In addition to the parallel guidance function, such a cord system, if properly biased by spring means, may also contribute to provide sufficient friction to allow parking of the bottom bar in suitable positions.
Even though such parallel guidance cord systems have proven to function well, they also render the screening device costly and complicated to install, and are not suitable for all fields of application. Another challenge is providing a well-defined unwound position of the screening body, that is, when the bottom bar should not be moved further downwards in the second longitudinal direction. In some screening devices, the bottom bar comes to a natural stop when it reaches the bottom of the frame in which the screening device is installed or alternatively a brake arrangement can be implemented, as in patent WO2019173880 . However, such natural stops are not always accessible in all installation positions of the roller screen.
Further examples of prior art documents include JP2006016815A which shows and describes a roll screen door with a windup shaft, guide rails, and a movable rail, with a stop mechanism holding the movable rail in a stopped state, and EP1223299A2 which shows and describes a roller blind with a rotating lock engaging in the roller blind guide which is transferred against spring force from a blocking position into a release position.
Thus, there is a desire to improve a roller screen of the type mentioned by way of introduction, with which the above drawbacks are more fully alleviated.

Summary of Invention

It is therefore the object of the invention to provide a roller screen by which the operational conditions are improved.
This and other objects are achieved by means of a roller screen of the type mentioned by way of introduction and further comprising a bottom stop mechanism is provided and configured to position and securely hold the bottom bar with the screening body in the unwound position, wherein the bottom bar comprises two opposite ends, each of the two opposite ends of the bottom bar being provided with an end device comprising: guiding and friction means configured to be arranged in the first track of the respective side rail and being provided with larger dimensions than the opening of the first track, and comprising at least one resilient element arranged on a fixed element and configured to press against at least one inner side of a flange of said track, and means of the bottom stop mechanism, said means comprising a resilient part biased in a direction parallel with and away from the bottom bar, and wherein the bottom stop mechanism further comprises a second part arranged in, at or on a bottom end of each the side rail, the second part comprising a recess, the second part being provided with a head portion located above the recess in the second longitudinal direction.
In this way, a flexible solution for a roller screen has been found in providing the bottom bar with an end device which partly provides for suitable friction and guidance during movement, partly comprises one part of the bottom stop mechanism to cooperate with a second part in, at or on the bottom end of the side rail. This presents a simple, yet reliable structure. In particular as regards the bottom stop mechanism, this involves mutual engagement between the resilient part and the recess located below the head portion of the second part.
In a presently preferred embodiment, the second part of the bottom stop mechanism is arranged outside of the at least first track of the side rail, preferably in a separate second track. In this way, proper functioning of the bottom stop mechanism on one hand and the guiding and friction means on the other is not complicated or even impeded.
In one embodiment, the guiding and friction means of the respective end device are connected adjustably to each end of the bottom bar, particularly adjustably with respect to a longitudinal direction of the bottom bar. This provides for optimum adjustability possibilities.
In an alternative embodiment, the bottom bar and the guiding and friction means are fixed with respect to one another, and wherein the guiding and friction means of each end device are adjustable within the track of the respective side rail. In this way, increased flexibility is obtained.
The resilient part of the bottom stop mechanism means of the end device advantageously comprises an upper inclined surface adapted for abutment with an edge of the recess of the second part of the bottom stop mechanism. This design provides for a particularly smooth operation.
In another embodiment, the resilient part comprises a lower inclined surface adapted for sliding abutment with an inclined portion of the second part during movement of the bottom bar in the unwinding direction of the roller screen. Also this means that operation is facilitated.
In a further embodiment, the resilient part comprises an arm with a point of rotation and a biasing element, such as a spring, positioned at an opposite, free end of the arm. This is a mechanically simple and reliable solution.
In another embodiment, he resilient part is movable between a resting position and a maximally flexed position, and wherein the resilient element in the maximally flexed position is positioned at a distance from an inner side of a leg of the side rail. In this way, it is at all times ensured that no chafing or friction occurs.
In a further presently preferred embodiment, each of the side rails comprises a second track separated from said first track by said protruding flange and delimited by said leg and a bottom flange, and wherein the resilient part of the bottom stop mechanism means is configured to be movable in said second track. Thus, a compact configuration of the side rail is ensured while at the same time, the operation of the individual parts is not affected. In a further development of this embodiment, the second track in a mounted condition of the roller screen is arranged closer to an inner wall of the building aperture than the first track. This increases the utilisation of the available space even further.
In another presently preferred embodiment, the guiding and friction means and the means of the bottom stop mechanism are configured such that release of the means at one end of the bottom bar will entail release of the means at the other end of the bottom bar when the bottom bar is brought to an angle relative to the first longitudinal direction. This prevents that the bottom bar gets stuck if inadvertently brought to a skew position.
Other presently preferred embodiments and further advantages will be apparent from the subsequent detailed description and drawings.

Brief Description of Drawings

In the following description embodiments of the invention will be described with reference to the schematic drawings, in which

Fig. 1 is a perspective view of a roller screen in an embodiment of the invention mounted at a building aperture;
Fig. 2 shows an exploded plan view of a roller screen in an embodiment of the invention before assembly;
Fig. 3 shows an enlarged view of a part of a bottom element of the roller screen of Fig. 2, corresponding to the detail III shown in Fig. 2;
Fig. 4 is a schematic cross-sectional view of a top casing and a mounting bracket of the roller screen of Fig. 2;
Fig. 5 is a partial perspective view of the upper left-hand corner of the roller screen in an embodiment of the invention;
Fig. 6 is partial perspective, cross-sectional view of the roller screen in an embodiment of the invention;
Fig. 7 is an exploded perspective view of a side rail, a bottom bar and an end device of an embodiment of a roller screen in an embodiment of the invention;
Fig. 8 is an exploded view of the end device of Fig. 7;
Fig. 9 is a cross-sectional view of a side rail with parts of an end device of the roller screen in an embodiment of the invention;
Fig. 10 shows a schematic plan view of details of the bottom stop mechanism of the roller screen in an embodiment of the invention;
Fig. 11 is a partial perspective view of the lower left-hand corner of the roller screen in an embodiment of the invention;
Fig. 12 is a view corresponding to Fig. 2, of an alternative embodiment of the roller screen according to the invention; and
Fig. 13 is an exploded perspective view of details of the roller screen of Fig. 12.

Description of Embodiments

In the following detailed description, a preferred embodiments of the present invention will be described. However, it is to be understood that features of the different embodiments are exchangeable between the embodiments and may be combined in different ways, without departing from the scope of the appended claims. It may also be noted that, for the sake of clarity, the dimensions of certain components illustrated in the drawings may differ from the corresponding dimensions in real-life implementations.
It is noted that terms such as "up", "down", "left-hand", "right-hand", "exterior", "interior", "outer", "inner" are relative and refers to the viewpoint in question.
Referring initially to Fig. 1, a first embodiment of a screening arrangement in the form of a roller screen 1 mounted at a building aperture 3 in an inclined wall 35 is shown.
The roller screen 1 may be in the form of an insect net or the like. The roller screen 1 may be for shielding a building aperture 3, in particular a window area in an inclined wall or an inclined wall. The building aperture 3 is delimited by side inclined walls 31 and 32, an upper inclined wall 33 and a lower inclined wall 34 and the roller screen 1 is mounted on the internal side of the building aperture 3 on the inclined wall 35. A periphery is defined by surface portions of the inclined wall 35, i.e. extending in a plane substantially perpendicular to the side inclined walls 31, 32, the upper inclined wall 33 and the lower inclined wall 34.
The roller screen 1 may also be mounted directly on a sash 21 of a roof window 2 mounted in the building aperture 3. The sash 21 comprises side elements 22, a top element 23 and a bottom element 24, and the roller screen 1 is mounted on the internal side of the sash 21 facing the interior of a building in which the roof window 2 is mounted.
The roller screen 1 comprises a supply condition and a condition of use. Referring also to Fig. 2, the roller screen 1 further comprises a top casing 4, a bottom element 5 and first and second side rails 6, 7. In an assembled condition, as shown in Fig. 1, the top casing 4, bottom element 5 and first and second side rails 6, 7 form a rectangular frame where the top casing 4 and a bottom element 5 extending substantially in parallel to each other in a first longitudinal direction defining, in the condition of use, a width direction, and where the first and second side rails 6, 7 extend substantially in parallel to each other in a second longitudinal direction defining, in the condition of use, a height direction. The first longitudinal direction is substantially perpendicular to the second longitudinal direction. The first and second side rails 6, 7 thus connect the top casing 4 and the bottom element 5. The thus formed rectangular frame delimits an aperture 100. Furthermore, the roller screen 1 may comprise connection elements or inserts 40 configured to connect the top casing to the side rails and corner connection elements or inserts 60 configured to connect the bottom element to the side rails.
The roller screen 1 may further comprise extension elements 8, 9 for the first and second side rails 6, 7. The extension elements 8, 9 makes it possible to extend the side rails 6, 7 such as to fit the roller screen 1 to the size of the building aperture 3 or roof window 2 during mounting. The roller screen 1 may also comprise further connection elements or inserts similar to the connection elements 40 configured for connecting the side rails and the extension elements.
The top casing 4, bottom element 5, side rails 6, 7 and, if provided, the extension elements 8, 9 are intended to be arranged along the edges of the building aperture 3 or along the edges of the sash 21 of the roof window 2. An arrestable locking device for engagement with a retainer device may be provided at the bottom of each guide rail of the side rails 6, 7.
The roller screen 1 further comprises a screening body in the form of a lightweight flexible screen 10, which may be made of wire mesh 15. The screen of wire mesh 15 is an insect net adapted to cover an aperture of a window in order to prevent insects, leaves, debris, birds and the like from entering the building while a flow of fresh air into the building is permitted. The screen of wire mesh 15 may be a wire net of metal, fiberglass and the like synthetic fibers in a mesh or a plastic mesh made from polypropylene, polyethylene, nylon, PVC or PTFE or the like materials. Preferably, the screen of wire mesh 15 is a PVC coated insect net of fiberglass. In order to facilitate handling of the roller screen in a storage condition, the screen of wire mesh 15 is preferably made so flexible that it may be wound up for easier handling during storage outside the season or in the supply condition of the roller screen 1. The side edges of the screen 10 are guided in tracks (not shown in detail) in the side rails 6, 7, and if present, the extension elements 8, 9. The screen 10 of wire mesh 15 thus covers the aperture 100 of the rectangular frame completely in the condition of use.
The roller screen 1 further comprises a spring-biased roller bar 12 (cf. Fig 4) arranged in the top casing 4. The top casing 4 and the roller bar 12 are to be mounted at an upper edge of the building aperture 3 or roof window 2.
A bottom bar 13 is arranged at a bottom edge 11 of the flexible screen 10. The flexible screen 10 is designed to be wound and unwound from a screening position to a non-screening position, and vice versa, by winding and unwinding, respectively, the flexible screen 10 on the roller bar 12. The bottom bar 13 comprises at its opposite ends guide members slidable in guide tracks of the side rails 6, 7. The bottom bar 13 comprises a handle portion 14 intended to be gripped by a user when operating the roller screen 1. Although not described in detail here, the handle portion 14 is provided in the form of a longitudinal recess in the bottom bar 13 to allow a user to introduce finger/s to operate the screening arrangement 1.
Referring also to Fig. 3, the bottom element 5 further comprises an opening 18 for receiving a fastening element 19, such as a screw, for fixing the bottom element 5 to the inclined wall 35. The bottom element 5 is temporarily fixed to the inclined wall 35 in a first, intermediate position. Following sideways adjustment of the bottom element 5 and of the top casing 4, such that the rectangular shape is retained, the bottom element 5 and consequently the top casing are fixed in a second, final position. The opening 18 is an oblong opening allowing for adjusting the sideways position of the assembled rectangular frame before fastening the fastening element 19 completely and thus fixing the position of the bottom element 5 and of the other components with respect to the inclined wall 35. Alternatively, the opening 18 may be a round opening.
Furthermore, at least one of the side elements 6 and 7 may in a similar manner comprise an opening for receiving a further fastening element for fixing the side element 6, 7 to the inclined wall 35. Also, the extension elements 8, 9, where provided, may also comprise such an opening.
Referring now to Fig. 4, the top casing 4 comprises a rear surface 41, a front surface 42 and an upper surface 43. The rear surface 41 abuts the inclined wall 35 in a mounted condition of the roller screen 1. The front surface 42 faces away from the inclined wall 35 in a mounted condition of the roller screen 1. The upper surface 43 connects the rear surface 41 and the front surface 42. The top casing 4 defines an interior 49 in which the roller bar 12 is accommodated. The flexible screen 10 is at one end portion connected to the roller bar 12 and wound on the roller bar 12 such that most of the flexible screen 10 is also accommodated in the top casing 4 in the non-screening position. Fig. 4 is a simplistic view, not showing the connection of the flexible screen 10 to the bottom bar 13. An opening 48 allows insertion of the flexible screen 10 into the interior 49 of the top casing 4.
The top casing 4 further comprises a track 44 provided in the rear surface 41 of the top casing 4 in a position adjacent to, close to or near the upper surface 43 of the top casing 4. The track 44 is adapted for receiving a part of a mounting bracket 16 to be described further below. The track 44 extends in a longitudinal direction of the top casing 4 between opposite longitudinal ends 47a and 47b (Fig. 2) of the top casing 4. The track 44 may extend all the way or part of the way, preferably centrally, between the opposite longitudinal ends 47a and 47b of the top casing 4.
Referring now to Figs 5 to 11, further details of the roller screen 1 will be described in detail. Not all elements previously described will be mentioned in detail, including the top casing 4 defining a first longitudinal direction and in which a spring-biased roller bar 12 is arranged rotatably and the bottom bar 13 configured to extend substantially in parallel with the top casing 4 and being manually operable. As in the above, two side rails 6 and 7, each extending in a second longitudinal direction, substantially perpendicular from a respective end of the top casing 4, are provided; reference to the second side rail 7 as "the side rail" will be made.
The side rail 7 thus comprises at least a first track 71 with an opening 711 and delimited by a front flange 70, a leg 74, a protruding flange 72 and an upstanding flange portion 73a. The opening 711 faces a counterpart opening of the first side rail 6.
Although not shown in detail, the two side edges of the screening body 10 are guided in the respective side rails the two side edges of the screening body are provided with discrete or continuously positioned thickenings guided in the first track 71 and having a transverse dimension larger than the opening 711. As in the above description of Figs 1 to 4, the screening body 10 has its first end portion connected to the roller bar 12 and its second end portion connected to the bottom bar 13.
In order to ensure that the user experiences a well-defined end position, when the screening body 10 has been moved, in the second longitudinal direction, from its non-screening position to its screening position in which the screening body 10 is unwound from the roller bar 12 and covers the building aperture, a bottom stop mechanism is provided, which is configured to position and securely hold the bottom bar 13 with the screening body in the unwound position. The bottom stop mechanism will be described in further detail below.
The bottom bar 13 has two opposite ends 130. At each of the two opposite ends 130, an end device 50 is provided. The end device 50 comprises guiding and friction means generally designated 51 configured to be arranged in the first track 71 of the side rail 7. The guiding and friction means 51 are provided with larger dimensions than the opening 711 of the first track 71 such that they are prevented from being unintendedly removed from the track 71 of the side rail 7.
The guiding and friction means 51 comprise at least one resilient element 512, 513 arranged on a fixed element 511 and are configured to press against at least one inner side of a flange of said track 71. By the term "inner side" is meant a surface facing an interior, or a cavity, of the first track 71. In principle, only one resilient element could be provided, to press against the inner side of an arbitrary flange of the track 71. It is preferred that at least one resilient element presses against the front flange 70. In the embodiment shown, two resilient elements 512 and 513 are provided to press against the inner side of the front flange 70 and the protruding flange 72, respectively, delimiting the track 71 of the side rail 7. In order to provide the bias required to obtain the pressing action, a separate spring 514 is connected to the fixed element 511. It is also conceivable to provide the resilient element or elements with integrated biasing means.
In the embodiment shown, the guiding and friction means 51 and the means 52 of the bottom stop mechanism are connected to at least one common element 53, 54 of the end device 50. Here, a common base element 53 and a common transition element 54 are provided.
It is preferred that the guiding and friction means 51 of the respective end device 50 are connected adjustably to each end of the bottom bar 13, particularly adjustably with respect to a longitudinal direction of the bottom bar 13. In the embodiment shown, the common base element 53 is provided with a central portion 530 from which a holding portion 531 for the guiding and friction means 51 and an insertion portion 532 protrude. The adjustable connection between the end device and the bottom bar 13 is here achieved by the insertion portion 532 of the common base element 53, which is slidable in suitable reception means such as a track (not shown) in the bottom bar 13. Alternatively, the bottom bar and the guiding and friction means are fixed with respect to one another, and wherein the guiding and friction means of each end device are adjustable within the track of the respective side rail.
The end device 50 also comprises means 52 of the bottom stop mechanism and include a resilient part 52 biased in a direction parallel with and away from the bottom bar 13. In the embodiment shown, the resilient part 52 is connected to the common base element 53 of the end device 50.
The bottom stop mechanism further comprises a second part arranged in, at or on a bottom end of each the side rail 7. In the embodiment shown, the second part is formed in the bottom connection corner 60 comprising also a second leg 62 and a third leg 63 arranged to be inserted into the side rail 7 and the bottom element 5, respectively. As shown, the second part of the bottom stop mechanism is arranged outside of the at least first track 71 of the side rail, here in a separate second track 75, which is furthermore arranged closer to an inner wall of the building aperture than the first track 71.
The bottom connection corner 60 comprises a recess 611 provided with a head portion 612 located above the recess 611, as seen in the second longitudinal direction.
The resilient part 52 of the bottom stop mechanism means of the end device 50 comprises an arm with a point of rotation 522 and a biasing element, such as a spring 521, positioned at an opposite, free end of the arm. Furthermore, an upper inclined surface 523 is provided, which is adapted for abutment with an edge of the recess 611 of the second part 60 of the bottom stop mechanism. In this way, a safe engagement which is still easy to release is obtained.
In order to ease operation further, the resilient part 52 comprises a lower inclined surface 524 adapted for sliding abutment with an inclined portion 613 of the second part during movement of the bottom bar 13 in the unwinding direction of the roller screen 1. The inclined portion 613 thus forms a ramp for the resilient part 52, and a well-defined stop action is achieved when the resilient part 52 is moved outwards, away from the bottom bar 13, to allow the click into engagement with the recess 611 below the head portion 612.
During the movement in the winding and unwinding direction, the resilient part 52 of the bottom stop mechanism means is movable in the second track 75, substantially without touching the inner sides of the side rail 7. In turn, this means that the resilient part 52 is movable between a resting position and a maximally flexed position, and wherein the resilient element in the maximally flexed position is positioned at a distance from an inner side of the leg 74 of the side rail 7.
In order to improve the user experience further, the guiding and friction means 51 and the means 52 of the bottom stop mechanism are configured such that release of the means at one end of the bottom bar 13 will entail release of the means at the other end of the bottom bar 13 when the bottom bar is brought to an angle relative to the first longitudinal direction.
An alternative embodiment of the roller screen 1 according to the invention is shown in Fig. 12. The roller screen 1 differs in that the bottom bar 13 delimits the handle portion14 at a central section thereof, thereby encouraging a user of the roller screen to interact with the bottom bar 13 at the center of it, thereby avoiding kinking of the bottom bar 13 in the side rails 6, 7. The handle portion 14 may be delimited in a plethora of ways, e.g. the bottom bar being extruded as a substantially solid bar wherein the handle portion 14 is formed by milling. In the shown embodiment the handle portion 14 is delimited by one insert 20, where the insert 20 comprises curved section, which delimits the handle portion 14.
Referring now also to Fig. 13, which shows an alternative embodiment of inserts, wherein the handle portion is delimited by a first insert 201 and a second insert 202. The inserts 20, 201, 202 in both embodiments may be configured to be accommodated within a longitudinal groove 131 of the bottom bar 13. The inserts 20, 201, 202 may be configured to be snapped into or slid into the longitudinal groove 131. At the ends 130 of the bottom bar 13, the end devices 50 may act as stops for the insert(s), 20, 201, 202.
The person skilled in the art realizes that the present invention by no means is limited to the preferred embodiments described above. On the contrary, many modifications and variations are possible within the scope of the appended claims.

List of reference numerals

1: roller screen
2: roof window
21 sash
22 side sash element
23 top sash element
24 bottom sash element
3: building aperture
31 side wall
32 side wall
33 top wall
34 bottom wall
35 inclined wall
4: top casing
40 top connection element
41 rear surface
42 front surface
43 upper surface
44 track
47a opposite end
47b opposite end
48 opening
49 interior
5: bottom element
6: side rail
7: side rail
70 front flange of side rail
71 first track
711 opening of first track
72 protruding flange
73a upstanding flange portion
74b depending flange portion
75 second track
76 bottom flange
77 side flange
78 third track
791 first wall flange
792 second wall flange
8: extension element
9: extension element
10: screening body / flexible screen
11: bottom edge
12: spring-biased roller bar
13: bottom bar
130 end
131 groove
14: handle portion
15: wire mesh
16: mounting bracket
17: fastening means
18: opening in bottom element
19: fastening element
20: insert element
201 first insert
202 second insert

50: end device
51 guiding and friction means
511 fixed element
512 first resilient element
513 second resilient element
514 spring (of guiding and friction means)
52 bottom stop mechanism means / resilient part
521 spring (of resilient part)
522 rotatable connection
523 upper inclined portion
524 lower inclined portion
53 common base element
531 holding portion
532 insertion portion
54 common transition element

60: bottom connection corner / second part
61 first leg
611 recess
612 head portion
613 inclined portion
62 second leg
63 third leg

100: aperture

Claims

A roller screen (1), in particular in the form of an insect net or the like, for shielding a building aperture (3), in particular a roof window area, which roller screen comprises:
a top casing (4) defining a first longitudinal direction and in which a spring-biased roller bar (12) is arranged rotatably,

a bottom bar (13) configured to extend substantially in parallel with the top casing (4) and being manually operable,

a first side rail (6) and a second side rail (7), each extending in a second longitudinal direction, substantially perpendicular from a respective end of the top casing (4) and comprising at least a first track (71) with an opening (711) and delimited by a front flange (70), a leg (74), a protruding flange (72) and an upstanding flange portion (73a), the openings of the first side rail (6) and the second side rail (7) facing one another, and

a screening body (10) having two side edges and a predefined length between a first end portion connected to the roller bar (12) and a second end portion connected to the bottom bar (13), said screening body (10) being movable in the second longitudinal direction between a non-screening position and a screening position in which the screening body (10) is unwound from the roller bar (12) and covers the building aperture, the two side edges of the screening body being provided with discrete or continuously positioned thickenings guided in the first track (71) and having a transverse dimension larger than the opening (711),

wherein a bottom stop mechanism is provided and configured to position and securely hold the bottom bar (13) with the screening body in the unwound position,

wherein the bottom bar (13) comprises two opposite ends (130), each of the two opposite ends (130) of the bottom bar (13) being provided with an end device (50) comprising:
- guiding and friction means (51) configured to be arranged in the first track (71) of the respective side rail (6, 7) and being provided with larger dimensions than the opening (711) of the first track (71), and comprising at least one resilient element (512, 513) arranged on a fixed element (511) and configured to press against at least one inner side of a flange (70, 72) of said track (71), and

- means (52) of the bottom stop mechanism, said means comprising a resilient part (52) biased in a direction parallel with and away from the bottom bar (13),

characterised in that

the roller screen is configured for installation in an inclined wall,

that the bottom stop mechanism further comprises a second part (60) arranged in, at or on a bottom end of each the side rail (7), the second part comprising a recess (611), the second part (60) being provided with a head portion (612) located above the recess (611) in the second longitudinal direction, and

that the bottom stop mechanism involves mutual engagement between the resilient part and the recess located below the head portion of the second part.
A roller screen according to claim 1, wherein the second part (60) of the bottom stop mechanism is arranged outside of the at least first track (71) of the side rail, preferably in a separate second track (75).
A roller screen according to any of the preceding claims, wherein the guiding and friction means (51) of the respective end device (50) are connected adjustably to each end of the bottom bar (13), particularly adjustably with respect to a longitudinal direction of the bottom bar (13).
A roller screen according to any of claims 1 and 2, wherein the bottom bar and the guiding and friction means are fixed with respect to one another, and wherein the guiding and friction means of each end device are adjustable within the track of the respective side rail.
A roller screen according to any of the preceding claims, wherein the resilient part (52) of the bottom stop mechanism means of the end device (50) comprises an upper inclined surface (523) adapted for abutment with an edge of the recess (611) of the second part (60) of the bottom stop mechanism.
A roller screen according to any of the preceding claims, wherein the resilient part (52) comprises a lower inclined surface (524) adapted for sliding abutment with an inclined portion (613) of the second part (60) during movement of the bottom bar (13) in the unwinding direction of the roller screen (1).
A roller screen according to any of the preceding claims, wherein the resilient part (52) comprises an arm with a point of rotation and a biasing element, such as a spring (521), positioned at an opposite, free end of the arm.
A roller screen according to any of the preceding claims, wherein the resilient part (52) is movable between a resting position and a maximally flexed position, and wherein the resilient element in the maximally flexed position is positioned at a distance from an inner side of a leg (74) of the side rail (7).
A roller screen according to any of the preceding claims, wherein each of the side rails (7) comprises a second track (75) separated from said first track (71) by said protruding flange (72) and delimited by said leg (74) and a bottom flange (76), and wherein the resilient part (52) of the bottom stop mechanism means is configured to be movable in said second track (75).
A roller screen according to claim 9, wherein the second track (75) in a mounted condition of the roller screen is arranged closer to an inner wall of the building aperture than the first track (71).
A roller screen according to any of the preceding claims, wherein the side rails (6, 7) comprise extension elements (8, 9).
A roller screen according to any of the preceding claims, wherein a bottom element (5) is provided opposite to the top casing (4) such that a rectangular frame comprising the top casing (4), the bottom element (5), the first and second side rails (6, 7) and optionally extension elements (8, 9) such that the top casing (4) and the bottom element (5) extend substantially in parallel to each other, and the first and second side rail (6, 7), optionally with extension elements (8, 9), extend substantially in parallel to each other and connecting the top casing (4) and the bottom element (5), the extension elements (8, 9) being preferably provided with substantially identical cross-section as the side rails (6, 7).
A roller screen according to any of the preceding claims, wherein the guiding and friction means (51) and the means (52) of the bottom stop mechanism are configured such that release of the means at one end of the bottom bar (13) will entail release of the means at the other end of the bottom bar (13) when the bottom bar is brought to an angle relative to the first longitudinal direction.
A roller screen according to any of the preceding claims, wherein the guiding and friction means (51) and the means (52) of the bottom stop mechanism are connected to at least one common element (53, 54) of the end device (50), preferably comprising a common base element (53) and a common transition element (54).
A roller screen according to any of the preceding claims, wherein at least one resilient element (512, 513) is configured to press against the inner side of the front flange (70) delimiting the track (71) of the side rail (6, 7).
A roller screen according to any of the preceding claims, wherein a spring (514) is connected to the fixed element (511).
A roller screen according to any one of the preceding claims, wherein a first resilient element (512) and a second resilient element (513) are connected to a common fixed element (511), configured to press against the inner side of the front flange (70) and the protruding flange (72) delimiting the track (71) of the side rail (6, 7).
A roller screen according to any of the preceding claims, wherein the bottom bar (13) comprises means for delimiting a handle portion (14) for gripping the bottom bar (13) at a central section thereof, said means preferably comprising at least one insert element (20; 201, 202) accommodated within a longitudinal groove (131) of the bottom bar (13).