Guide cartridge of the flexible fabric of a roller blind and a roller blind using said guide cartridge

EP4689342A1Pending Publication Date: 2026-02-11BAT SPA
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Patent Information

Application Number
EP2024841281
Authority / Receiving Office
EP · EP
Patent Type
Applications
Current Assignee / Owner
Priority Date
2024-01-25
Filing Date
2024-12-20
Publication Date
2026-02-11

AI Technical Summary

Technical Problem

Existing roller blind guide assemblies suffer from instability, deformation over time, unsightly large openings, and ease of dust and foreign body entry, which affect aesthetics and functionality, assembly, and maintenance.

Method used

A guide cartridge with slidably and telescopically connected elements using elastic means, featuring smaller openings and a stable, aesthetically pleasing design that reduces dust and foreign body ingress, facilitating easy assembly and maintenance.

Benefits of technology

The guide cartridge provides enhanced stability, reduced maintenance needs, and improved aesthetics by minimizing opening sizes and preventing dust entry, while maintaining smooth operation and ease of assembly.

✦ Generated by Eureka AI based on patent content.

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Abstract

A guide cartridge (1) of the flexible fabric (2) of a roller blind (50) during raising and lowering which comprises: a first profile (8) which extends according to a predominantly longitudinal direction (Y); a second profile (9) which also extends according to a predominantly longitudinal direction (Y) and is slidably accommodated within the first profile (8), in which there is a longitudinal slot (10) configured to accommodate within it a side edge (6) of the flexible fabric (2); elastic means (11, 16) which are accommodated in the first profile (8) to elastically constrain the second profile (9) within the first profile (8). A roller blind (50) comprising a frame (51) in turn comprising a pair of side uprights (52) surmounted by a box (53) in which a roller (54) is housed for winding a flexible fabric (2) and each of the side uprights (52) accommodates a guide cartridge (1).
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Description

[0001] GUIDE CARTRIDGE OF THE FLEXIBLE FABRIC OF A ROLLER BLIND AND A ROLLER BLIND USING SAID GUIDE CARTRIDGE.

[0002] DESCRIPTION

[0003] The invention concerns a guide cartridge for the raising and lowering of the flexible fabric of a roller blind.

[0004] The invention also concerns a roller blind using the aforementioned guide cartridge.

[0005] It is well known that in order to control the entry of light or air into indoor rooms or, more simply, to prevent them from being observed from the outside, it is customary to apply blinds of various kinds to windows, of which so-called roller blinds are currently the most widely used.

[0006] Blinds of this type comprise a frame that is fitted into a window compartment, in which there are two uprights that are fixed to the sides of the window compartment, and a box placed above the uprights and attached to the upper edge of the window compartment, which houses a roller onto which a flexible fabric is wound.

[0007] Within the respective uprights guide means are housed along which the side edges of the flexible fabric slide during lowering or raising when manual or motorised drive means rotate the roller onto which the flexible fabric is wound. The guide means of the prior art used in known roller blinds have a number of recognised limitations and drawbacks, both in terms of aesthetics and function, also with regard to the possibility of performing the necessary assembly and maintenance operations.

[0008] Patent document DE 102016125383A1 is known, for example, in which a ZIP- guided sun blind is described wherein the flexible fabric is guided by a guide assembly which, as can be seen in particular in Figures 1 and 2 annexed to said patent document, comprises an insert 32 housed in a support profile 16 which in turn is inserted in a respective guide rail 10.

[0009] The coupling of each insert 32 into the respective support profile 16 and of this into the respective guide rail 10 takes place by means of a snap-fit system by elastically deforming special coupling means, which are made as a single piece in the support profile 16 in the guide rail 10.

[0010] This requires the various elements, and at least the support profile 16 and the guide rail 10 together with the coupling means, to be made of elastically yielding material, preferably by moulding or extrusion, so that they are sufficiently elastic for easy assembly and disassembly.

[0011] However, this has the disadvantage that, when the elements are assembled and especially if they are of considerable length, they display a certain degree of instability during use.

[0012] Moreover, they tend to become permanently deformed over time, especially if they have been disassembled and reassembled for repairs, maintenance or cleaning.

[0013] In addition, the various elements must be made with significantly wide openings in order to be able to fit them together easily without having to deform them excessively, and this has the drawback that they are often unsightly, especially considering that they are installed exposed along the uprights of the roller blind frame inserted in the window compartment.

[0014] Particularly, it is observed in Figures 1 and 2 and in the other figures annexed to the cited patent document that the significant width of the opening made in the support profile 16 through which the insert 32 is snap fitted promotes the entry and accumulation of dust and foreign bodies in the support profile 16 with the drawback of progressively reducing the sliding of the insert 32 and the elasticity of the springs 30 that elastically constrain it to the support profile 16. The present invention aims at creating a cartridge for guiding the flexible fabric of a roller blind during raising and lowering that does not have the drawbacks that have been listed.

[0015] In addition, the invention also relates to a guide assembly into which such a cartridge is inserted and, likewise, to a roller blind that employs the aforementioned guide assembly with the aforementioned cartridge.

[0016] In particular, the first aim is to create a guide cartridge for the flexible fabric of a roller blind wherein the constituent elements are not connected to each other by means of snap-fit coupling means.

[0017] Advantageously, this aspect makes it possible to create a guide cartridge that exhibits greater dimensional stability than guide assemblies of the prior art.

[0018] As a second aim, it is desired to obtain the cartridge of the invention with smaller dimensions and also openings communicating with the external environment, in particular the openings along which the side edges of the flexible fabric slide, which are smaller in size with respect to guide assemblies of the prior art.

[0019] Advantageously, this aspect reduces the entry of dust and foreign bodies into the cartridge, which retains its efficiency over time and does not require or needs less cleaning and / or maintenance.

[0020] Last but not least, an aim is to ensure that the guide cartridge of the invention, compared to guide assemblies of the prior art, is easier to assemble and disassemble.

[0021] Advantageously, this aspect reduces the costs of any necessary maintenance work.

[0022] The above-mentioned aims are achieved by a cartridge for guiding the raising and lowering of the flexible fabric of a roller blind, the main features of which are described in claim 1 to which reference will be made.

[0023] Other features of the guide cartridge of the invention are described in the dependent claims.

[0024] The listed purposes and advantages will be better highlighted below during the description of a preferred, but not exclusive, embodiment of the guide cartridge of the flexible fabric of a roller blind according to the invention and of a roller blind using said guide cartridge, also according to the invention, which are provided below for illustrative purposes only, and not as a limitation, by reference to the accompanying drawings in which:

[0025] - Figure 1 shows an axonometric view of the guide cartridge of the flexible fabric of a roller blind, said cartridge and said blind both being the subject matter of the invention;

[0026] - Figure 2 shows the guide cartridge of Figure 1 in which the inner part is partially removed from the outer part;

[0027] - Figure 3 shows the guide cartridge of Figure 1 in which the two constituent parts are separated from each other;

[0028] - Figure 4 shows the guide cartridge of the invention associated with a structural part of the frame of the roller blind of the invention;

[0029] - Figure 5 shows the guide cartridge of Figure 4 partially removed from the structural part of the frame;

[0030] - Figure 6 shows the guide cartridge of Figure 4 totally removed from the structural part of the frame;

[0031] - Figure 7 shows an axonometric view of the guide cartridge of the invention and its elastic elements shown in a separate position from the guide cartridge;

[0032] - Figures 7a to 7c show cross-sectional views of three different stages of inserting the elastic elements of Figure 7 into the guide cartridge;

[0033] - Figures 8 and 9 show the cross-sections of a structural part of the roller blind of the invention in two different operating positions;

[0034] - Figures 10 and 11 show the cross-sections of Figures 8 and 9 in each of which the guide cartridge is housed in two different operating positions;

[0035] - Figure 12 shows a schematic axonometric view of the roller blind of the invention.

[0036] The guide cartridge according to the invention is shown in the three different views in Figures 1 to 3 and also in Figures 4 to 6 wherein it is collectively referred to as 1 and performs the function of guiding the flexible fabric 2 of a roller blind 50, both shown in Figure 12, during raising and lowering.

[0037] According to the invention, the guide cartridge 1 comprises a first profile 8 which extends according to a predominantly longitudinal direction Y and a second profile 9 which also extends according to the same predominantly longitudinal direction Y and is accommodated smoothly within the first profile 8, as can be seen particularly in Figures 1 and 2.

[0038] A longitudinal slot 10 is made in the second profile 9, as observed in Figures 1 to 3, and is configured to accommodate within it a side edge 6 of the flexible fabric 2, as can be seen in Figures 10 and 11 .

[0039] The longitudinal slot 10 has a very limited width, as it is sufficient to allow the side edge 6 of the flexible fabric 2 to slide, which has a very limited thickness, on the order of a few millimetres.

[0040] Finally, there are elastic means 11, which can be seen in Figures 7 and 7a to 7c, accommodated in the first profile 8 and which elastically constrain the second profile 9 within the first profile 8.

[0041] In particular, with regard to the second profile 9 it comprises a projecting core 13 extending along the full length thereof and along which the longitudinal slot 10 is made, which, as mentioned above, accommodates the side edge 6 of the flexible fabric 2.

[0042] With regard to the longitudinal slot 10 it can be seen, particularly in Figures 7a to 7c, that it communicates with a longitudinal chamber 14 that is made in the projecting core 13 undercut by the same longitudinal slot 10 and, as can be seen in Figures 10 and 11 , it accommodates a stop body 15 that is associated with the side edge 6 of the flexible fabric 2.

[0043] The width of the stop body 15 measured transverse to the longitudinal slot 10 is greater than the transverse width of the longitudinal slot 10 itself and therefore, after it has been inserted into the longitudinal slot 10, the stop body 15 cannot exit therefrom if, as can be seen in Figure 11 , a tensile force T applied to the flexible fabric 2 raises the second profile 9 from the bottom wall 8a of the first profile 8.

[0044] This ensures that, in the event of stresses coming from outside and acting against the flexible fabric 2, which will be discussed below, the side edges 6 of the flexible fabric 2 itself remain constrained to the second profile 9 within the longitudinal slot 10.

[0045] With regard to the elastic means 11 observed in Figure 7, for the sake of clarity of presentation they have been shown in an exploded view above the first profile 8 and are aligned one after the other to the side of the projecting core 13

[0046] In the operating position, however, the elastic means 11 are inserted into the first profile 8, as can be seen in the cross-section of the guide cartridge 1 shown in Figure 7c, where they are housed on either side of the projecting core 13 of the second profile 9.

[0047] In particular, according to the preferred embodiment described herein, the elastic means 11 comprise a plurality of elastic foils 16 which within the first profile 8 are arranged along both sides of the projecting core 13 and are aligned one after the other and spaced apart from each other, in exactly the same configuration which, as mentioned above, for reasons of clarity of presentation is shown in an exploded view in Figure 7.

[0048] It can be observed that each elastic foil 16 is shaped according to a profile recalling the shape of the letter V and within the first profile 8 it has its apex 16a placed in contact with the first profile 8 within an undercut area thereof 17, while each of its shaped ends 16b is placed in contact with the second profile 9, as can be clearly seen in Figures 7a to 7c and 10 and 11 .

[0049] Of course, the elastic means may also be of a different kind in other embodiments.

[0050] Operationally, to assemble the guide cartridge 1 firstly, the first profile 8 and the second profile 9 are arranged coaxial to each other and aligned one after the other according to the longitudinal direction Y common to both, as can be seen in Figure 3.

[0051] In particular, the first profile 8 has a substantially U-shaped transverse profile and comprises a bottom wall 8a delimited by two side walls 8b spaced apart from each other and orthogonal to the bottom wall 8a, each having the bent end edge 8c facing the opposite side wall, and the second profile 9 having a substantially Q shaped transverse profile defined by the projecting core 13 and delimited by the side edges 9a.

[0052] It can also be observed in Figures 1 to 3 that the first profile 8 has a longitudinal opening 20 defined between its bent end edges 8c whose transverse dimension 20a is greater than the width of the stop body 15 associated with the side edge 6 of the flexible fabric 2 which is inserted into the longitudinal slot 10 of the second profile 9.

[0053] This allows the flexible fabric 2 to slide smoothly during raising and lowering, and since the longitudinal opening 20 faces outwards, its limited width also reduces the passage of light and the entry of dust and dirt into the guide cartridge 1.

[0054] The second profile 9 is then inserted into the first profile 8 whose side walls 8b smoothly accommodate the substantially play-free coupling of the side edges 9a of the second profile 9, as can be seen in Figure 2, up to the final coupling which can be seen in Figure 1 wherein the second profile 9 is totally accommodated in the first profile 8 with the side edges 9a in contact with the side walls 8b of the first profile 8.

[0055] Once the coupling is complete, the elastic means 11 are inserted into the first profile 8, in the case being described the elastic foils 16, by slightly spreading the side walls 8b of the first profile 8 and operating as shown in Figures 7a to 7c.

[0056] To facilitate the operation of spreading the side walls 8b in order to insert the elastic foils 16 into the first profile 8, this is made of plastic or another elastically deformable material.

[0057] On the other hand, the second profile 9 is preferably but not exclusively made of elastomer.

[0058] After insertion, the elastic foils 16 will be arranged aligned and spaced apart one after the other on either side of the second profile 9 and each will be arranged as shown in Figure 7c.

[0059] In particular, it can be seen in Figure 7c that for each elastic foil 16 the shaped ends 16b are placed in support of the second profile 9 and are constrained in the side area 18d of the first profile 8 comprised between its side wall 8b and the projecting core 13 of the second profile 9, while its vertex 16a is constrained in the undercut area 17 of the first profile 8 defined by the bent end edge 8c of the respective side wall 8b.

[0060] After assembly, the thrust of the elastic means 11, in particular of the elastic foils 16, keeps the second profile 9 normally in contact with the bottom wall 18a of the first profile 8 and the presence of the stop body 15, which contrasts undercut within the longitudinal slot 10, keeps the side edge 6 and the flexible fabric 2 normally extended during raising and lowering.

[0061] If for any reason the flexible fabric 2 is stressed by a force F which, as can be seen in Figure 11 , raises the second profile 9 from the bottom surface 8a of the first profile 8 and is generated, for example, when the wind thrust tends to “inflate” the flexible fabric 2, the elastic deformation of the elastic foils 16 absorbs the force F and prevents the flexible fabric 2 from being torn.

[0062] When the stress ceases, the elastic recovery of the elastic foils 16 brings the second profile 9 into contact with the bottom surface 8a, as can be seen in Figure 10.

[0063] In view of the foregoing, the guide cartridge 1 of the invention achieves the intended aims.

[0064] First of all, it has been shown that the elements comprising the guide cartridge 1 of the invention do not have snap-fit coupling means of attachment as they are connected to each other slidably and telescopically with the interposition of elastic means.

[0065] Advantageously, the absence of coupling elements required to connect the elements to each other gives the guide cartridge of the invention greater stability than guide assemblies of the known type that are equivalent to it, in particular compared to the guide assembly of the cited patent document.

[0066] Furthermore, the sliding connection between the elements comprising the guide cartridge 1 of the invention does not require the presence of large openings for mutual insertion and subsequent locking by means of snap-fit means, which is found in guide assemblies of the known type.

[0067] Advantageously, this entails the possibility of reducing the size of the guide cartridge 1 of the invention by giving a better aesthetic effect to the roller blind to which it is applied.

[0068] Finally, in the guide cartridge 1 of the invention the reduced dimensions of the width 20a of the longitudinal opening 20 of the first profile 8 facing the external environment, which will be slightly larger than the width of the longitudinal slot 10 in which the side edge 6 of the flexible fabric 2 slides, reduces the possibility of the passage of light and the entry of dust and foreign bodies into the cartridge 1 thus preserving, over time, the smoothness and elasticity of the flexible fabric 2.

[0069] The roller blind 50 also according to the invention, which uses the guide cartridge 1 of the invention, is shown in an axonometric view in Figure 12 and comprises a frame 51 configured to be inserted into a window compartment, not shown, which in turn comprises a pair of side uprights 52 which are fixed to the sides of the window compartment and are surmounted by a box 53 which houses a roller 54 onto which the flexible fabric 2 is wound.

[0070] The guide cartridge 1 is housed in each of the uprights 52 and the crosssection of one of them with the cartridge 1 associated therewith is shown in Figures 10 and 11.

[0071] It is noted with particular reference to Figures 8 to 11 and also Figures 4 to 6 that in each of the side uprights 52 there is a shaped body 55 which is removably associated with the respective side upright 52 by means of snap-fit means 57 and in which a longitudinal channel 56 is defined which accommodates the guide cartridge 1 according to the invention and already described.

[0072] The coupling of the guide cartridge 1 into the longitudinal channel 56 defined in the shaped body 55 and which is achieved when the first profile 8 of the guide cartridge 1 is telescopically inserted into the longitudinal channel 56 forms the guide assembly indicated overall with 100 and shown in the axonometric view of Figure 4.

[0073] The longitudinal channel 56 has a substantially U-shaped transverse profile and comprises a base wall 56a delimited by two side walls 56b spaced apart from each other and each having the bent end edge 56c facing the opposite side wall and configured to telescopically and slidably accommodate the first profile 8 of the guide cartridge 1.

[0074] Thus, it is observed in Figures 4 to 6 and 10 and 11 that, when the first profile 8 is telescopically accommodated in the longitudinal channel 56, the walls 8a, 8b of the first profile 8 are in contact with the corresponding walls 56a, 56b of the longitudinal channel 56 and each bent end edge 8c of the first profile 8 is accommodated in the corresponding bent end edge 56c of the longitudinal channel 56.

[0075] In particular, it is observed in Figures 8 and 9 that between the bent end edges 56c of the longitudinal channel 56 a longitudinal slot 56d is defined which, when the first profile 8 is telescopically accommodated in the longitudinal channel 56, accommodates the longitudinal opening 20 present in the first profile 8, reducing it in width.

[0076] Indeed, it can be seen in Figures 10 and 11 that the longitudinal slot 56d represents the width 56e less than the width 20a of the longitudinal opening 20 of the first profile 8, as shown in Figures 10 and 11 , and is superimposed on the slot 20 present in the first profile 8 which has the internal projections 20b supporting the vertical walls 56f that delimit the longitudinal slot 56d.

[0077] Since the longitudinal channel 56 is made of metal material and is therefore rigid, this promotes the construction of its longitudinal slot 56d with the side walls 56f of the appropriate size to match it and fit it above the slot 20 of the first profile 8.

[0078] In addition, the width 56e of the longitudinal slot 56d may be made with the side walls 56f of the minimum dimensions to couple it and fit it above the slot 20 of the first profile 8 and to receive the sliding of the side edge 6 of the flexible fabric 2 since it will remain stable for the entire length of the longitudinal channel 56.

[0079] Since the longitudinal slot 56d faces outwards, the results of obtaining a more aesthetically pleasing roller blind 50 and limiting the entry of dust and other polluting substances into the guide cartridge 1 are achieved.

[0080] Finally, making the longitudinal channel 56 out of metal and therefore rigid material also has the advantage of accommodating and stabilising the guide cartridge 1 that is inserted inside it and whose first profile 8 is made of elastically deformable material.

[0081] Obviously, the width 56e of the longitudinal slot 56d can be reduced as desired without, however, exceeding the limit beyond which interference with the sliding of the flexible fabric 2 is created.

[0082] Operationally, when the user intends to raise or lower the flexible fabric 2, he operates manual or electrical means that rotate the roller 54 in the box 53 and raise or lower the flexible fabric 2 depending on the direction of rotation of the roller 54.

[0083] During raising or lowering, the side edges 6 of the flexible fabric 2 slide along the side uprights 52 and are guided by the guide cartridge 1 and in particular by the presence in the second profile 9 of the longitudinal slot 10 in which the side edges 6 slide.

[0084] The presence of the guide cartridge 1 also facilitates maintenance or repair operations of the roller blind 50.

[0085] In fact, unlike roller blinds of the prior art, for the disassembly of which it is necessary to separate the component parts by opening the coupling means with the risk of breakage, in the roller blind 50 of the invention it is sufficient to remove the guide cartridge 1 from the longitudinal channel 56 and replace it with a spare part.

[0086] Alternatively, if necessary, the cartridge 1 can be serviced by removably disassembling all its component parts and reassembling them after servicing by repeating the operations described above.

[0087] The lead times are shorter than those required for guide assemblies of the prior art which advantageously results in lower costs to be incurred.

[0088] On the basis of the foregoing, it is understood that the guide cartridge 1 and the roller blind 50 employing it, both of which are subject matter of the invention, achieve the purposes of the invention.

[0089] In the execution step, modifications and variations may be made to the cartridge and blind of the invention that have not been described or even shown in the accompanying drawings.

[0090] It is understood that, should such modifications or variations fall within the scope of the claims, they shall be deemed to be protected by this patent.

Claims

CLAIMS1 ) Guide cartridge (1 ) of the flexible fabric (2) of a roller blind (50) during raising and lowering, said guide cartridge (1 ) being characterised in that it comprises:- a first profile (8) extending in a predominantly longitudinal direction (Y), said first profile (8) being made of plastic or other elastically deformable material;- a second profile (9) which also extends in a predominantly longitudinal direction (Y) and is slidably accommodated within said first profile (8), said second profile (9) being provided with a longitudinal slot (10) made in said longitudinal direction (Y) and configured to accommodate within it a side edge (6) of said flexible fabric (2);- elastic means (11 , 16) which are accommodated in said first profile (8) and are configured to elastically constrain said second profile (9) within said first profile (8).2) Guide cartridge (1 ) according to claim 1 , characterised in that said first profile (8) has a substantially U-shaped transverse profile and comprises a bottom wall (8a) delimited by two side walls (8b) which are spaced apart from each other and each having the bent end edge (8c) facing the opposite side wall, and that said second profile (9) has side edges (9a) which, when it is accommodated in said first profile (8), are arranged slidably in contact with said side walls (8b) of said first profile (8).3) Guide cartridge (1 ) according to any one of the preceding claims, characterised in that said second profile (9) has a substantially Q shaped transverse profile which is defined by a projecting core (13) belonging to said second profile (9) and which extends along its entire length.4) Guide cartridge (1 ) according to claim 3, characterised in that said elastic means (11 , 16) are aligned one after the other along both sides of said projecting core (13).5) Guide cartridge (1 ) according to any one of claims 3 or 4, characterised in that along said projecting core (13) said longitudinal slot (10) is made, which accommodates within it said side edge (6) of said flexible fabric (2).6) Guide cartridge (1 ) according to any one of the preceding claims 3 to 5, characterised in that said longitudinal slot (10) communicates with a longitudinal chamber (14) formed in said projecting core (13) undercut bysaid longitudinal slot (10), said longitudinal chamber (14) being configured to accommodate a stop body (15) associated with said side edge (6) and slidably inserted into said longitudinal slot (10), the width of said stop body (15), measured transversely to said longitudinal slot (10), being greater than the width of said longitudinal slot (10).7) Guide cartridge (1 ) according to any one of claims 4 to 6, characterised in that said elastic means (11 ) comprise a plurality of elastic foils (16) which are arranged at both sides of said projecting core (13) and are aligned with each other and spaced apart one after the other.8) Guide cartridge (1 ) according to claim 7, characterised in that each of said elastic foils (16) is shaped according to a profile recalling the form of the letter V having the vertex (16a) placed in contact with an undercut area (17) present in said first profile (8) and each of the ends (16b) placed in contact with said second profile (9).9) Guide assembly (100) of the flexible fabric (2) of a roller blind (50) during raising and lowering characterised in that it comprises a shaped body (55) in which a longitudinal channel (56) is defined to accommodate a guide cartridge (1 ) according to any one of claims 1 to 8.10) Roller blind (50) comprising a frame (51 ) configured to be inserted into a window compartment and comprising a pair of side uprights (52) configured to be attached to the sides of said window compartment and surmounted by a box (53) in which a roller (54) is housed for winding a flexible fabric (2), characterised in that in each of said side uprights (52) there is a guide assembly (100) according to claim 9.11 ) Roller blind (50) according to claim 10, characterised in that said shaped body (55) is removably associated with said side upright (52) by means of snap-fit means (57).12) Roller blind (50) according to any one of claims 10 or 11 , characterised in that said longitudinal channel (56) has a substantially U-shaped transverse profile and comprises a bottom wall (56a) delimited by two side walls (56b) spaced apart from each other and each having the bent end edge (56c) facing the opposite side wall, said longitudinal channel (56) being configured to telescopically and slidably accommodate said first profile (8) of said guide cartridge (1 ).13) Roller blind (50) according to claim 12, characterised in that, whensaid first profile (8) is accommodated in said longitudinal channel (56), said walls (8a, 8b) of said first profile (8) are in contact with said corresponding walls (56a, 56b) of said longitudinal channel (56), and each bent end edge (8c) of said first profile (8) is accommodated in the corresponding bent end edge (56c) of said longitudinal channel (56).