EP4124718A1

EP4124718A1 - Fabric roller blind

Info

Publication number: EP4124718A1
Application number: EP22186915.9A
Authority: EP
Inventors: Luca Rossi; Luca Barbieri; Marco Donati
Original assignee: Palagina SRL
Current assignee: Palagina SRL
Priority date: 2021-07-26
Filing date: 2022-07-26
Publication date: 2023-02-01
Anticipated expiration: 2042-07-26
Also published as: EP4124718B1; IT202100019895A1

Abstract

Fabric roller blind, which comprises a support frame (2), a handle bar (5), slidably associated with the support frame (2), at least one first and one second synchronization chain (6, 7), connected to the support frame (2), mechanically connected to each other and subjected to a tensioning force (Ft).

The fabric roller blind also comprises adjustment means (8), placed within the handle bar (5), comprising a first adjustment body (9), connected to the first synchronization chain (6) and a second adjustment body (10), connected to the second synchronization chain (7) and mechanically connected to the first adjustment body (9).

The second adjustment body (10) comprises at least one longitudinal guide (12), and the first adjustment body (9) is slidably free to be moved along the longitudinal guide (12). At least one between the first adjustment body (9) and the second adjustment body (10) comprises at least one first pressure element (11), which determines a friction force (Fa) between the first adjustment body (9) and the second adjustment body (10), retaining the first adjustment body (9) constrained in an operative position along the longitudinal guide (12), with tensioning forces (Ft) between the synchronization chains (6, 7) lower than the friction force (Fa).

Description

Field of application

The present invention regards a fabric roller blind according to the preamble of the independent claim 1.
The present fabric roller blind is intended to be advantageously employed for adjustably closing openings in walls of buildings, in particular for windows, for doors, for French windows and similar doors/windows/shutters.
Preferably, the fabric roller blind, object of the present patent, is blind-like or mosquito netting of the type with vertical handle bar which closes and opens the opening by means of a horizontal translation of the same handle bar.
The blind, object of the present invention, is therefore inserted in the industrial field of production of doors/windows/shutters i.e. also in the field of production of sheets for sun protection, in the field of mosquito netting or similar applications.

State of the art

Known on the market are fabric roller blinds for closing openings of doors/windows/shutters (such as windows, doors or French windows), which are provided with a rolling shutter box, vertically fixed to a lateral upright of the building wall that defines the opening to be closed, and housing at its interior a roller on which a flexible covering sheet is susceptible of being wound and unwound.
The sheet usually has rectangular shape and is provided with a first lateral edge fixed to the roller and with a second lateral edge opposite the first lateral edge and fixed to a handle bar aimed to stretch the sheet itself during a movement thereof along a horizontal direction.
In addition, the blind usually comprises two guides placed horizontally along the corresponding upper and lower walls which define the opening and to which the handle bar is slidably constrained.
In particular, the handle bar usually comprises an aluminum section, which is closed at its upper and lower ends by two terminations slidably engaged in the respective horizontal guides.
Normally, each of the upper and lower horizontal guides is generally obtained by means of an aluminum section fixed to the upper or lower wall which defines the opening. Each aluminum section of the two guides is provided with a longitudinal slit which is extended along the extension of the same profile and which slidably houses, at its interior, the corresponding upper or lower termination of the handle bar.
The handle bar is movable by a user between an open position, in which it is side-by-side the rolling shutter box with the sheet completely wound around the roller, so as to free the opening to be screened, and a closed position, in which the handle bar is side-by-side the opposite lateral wall with the sheet substantially completely unwound from the roller and placed to close the opening.
In operation, starting from the open position, the user grips the handle bar and drives it along the horizontal guides up to the desired position, for example up to the closed position, in which the sheet is placed to totally cover the opening.
During this movement, the upper and lower terminals of the handle bar respectively slide along the upper and lower guides.
The blinds of known type described briefly up to now have in practice shown that they do not lack drawbacks.
A first drawback of the blinds of known type lies in the fact that such fabric roller blinds do not ensure a precise and uniform movement of the handle bar.
More in detail, in the event in which the handle bar is not gripped precisely at the midpoint of its height, but in a non-centered position, the latter is stressed to be moved more at the guide closer to where the handle bar has been gripped and, on the contrary, to a lesser extent at the guide further away from where the handle bar has been gripped. This causes a misalignment between the two ends of the handle bar, with one end of the handle bar more advanced in the direction of its movement and one end more retreated in the direction of its movement. Such misalignment of one end with respect to the other of the handle bar brings the handle bar to not be able to freely slide and hence to be blocked, and the windable fabric to be stretched in a non-uniform manner, forming folds that can in the long term also lead to deterioration and hence even to breakage of the sheet itself, in addition to being not very nice aesthetically, in particular if "fixed" on the fabric.
In order to at least partially overcome such drawbacks of the abovementioned prior art, fabric roller blinds were developed which are provided with means for aligning the terminations of the handle bar in order to maintain the aforesaid terminations vertically aligned during the movement of the same handle bar between the open and the closed positions.
For example, known from the patent EP 3670820 is a fabric roller blind, which is provided with the main members and components described above and with alignment means housed in the handle bar. More in detail, the means for aligning the aforesaid fabric roller blind comprise two guide chains (or "carriage" in the technical jargon of the field) that are connected to each other.
In particular, the alignment means comprise an upper guide chain and a lower guide chain, and each of which comprises a plurality of carriage elements, pivoted to each other in succession and capable of rotating with respect to each other only in one rotation sense, so as to attain, when extended, aligned in succession, a rigid member in the opposite rotation sense susceptible of attaining a guide for the sheet.
Each guide chain is extended between a first end, placed inside the cavity made on the handle bar and constrained to the first end of the other guide chain, and a second end.
More in detail, the second end of the upper guide chain is fixed to a first vertex of the support structure, placed on an upper portion of the latter, while the second end of the lower guide chain is fixed to a second vertex of the support structure, placed on a lower portion of the latter and opposite the first vertex. In this manner the two guide chains form an S shape.
When the blind is moved from the open position to the closed position, the guide chains are free to mutually slide, and in particular the lower guide chain is driven outside the vertical seat of the handle bar during the blind closing step, setting itself on the lower wall (usually the floor or a window sill) which delimits the opening to be screened, thus acting as lower guide for the sheet. Otherwise, during the blind opening step, the upper chain is driven outside the seat made in the handle bar, which is extended along the upper portion of the support structure.
The above-described fabric roller blind of known type also comprises adjustment means, adapted to allow the adjustment of the mutual position of the two guide chains. More in detail, following the installation step, it is necessary to adjust the mutual position between the two guide chains so as to allow the handle bar to be placed perfectly vertical, with its upper termination aligned with the opposite lower termination.
Indeed in the event in which one of the two guide chains is more tensioned than the other, this would tend to tilt the handle bar.
For such purpose, as mentioned above, the fabric roller blind of known type is provided with adjustment means, which comprise a first adjustment body, fixed to the upper guide chain, and a second adjustment body, fixed to the lower guide chain.
The two adjustment bodies are mechanically connected in an adjustable manner, in order to vary the mutual distance thereof and thus allow varying the distance between the first ends of the guide chains.
More in detail, the first adjustment body comprises a longitudinal guide, which is extended along a direction parallel to that of extension of the handle bar towards the second adjustment body and defines a through slot. In order to connect the first and the second adjustment body, a fixing screw is provided, which is fixed to the second adjustment body with the longitudinal guide of the first adjustment body interposed. In this manner, the screw is placed in abutment with its head against the longitudinal guide, while the stem is placed to traverse the through slot in order to be fixed to the second adjustment body. In this manner it is possible to fix the first and the second adjustment body at the desired mutual distance in order to selective approach and move away the first ends of the guide chains.
Such fabric roller blind of known type has in practice shown that it does not lack drawbacks.
A first drawback lies in the fact that in order to allow the correct adjustment of the guide chains, the handle bar must be made accessible for an operator, so as to allow the latter to adjust the distance between the first and the second adjustment body and fix, by means of the screw, the entire item at the end of adjustment. This means that the handle bar must be produced by means of two components which are connected together, for example a first C-section and a closure cover plate, or two C-sections connected to each other. The attainment of a handle bar by means of two separate elements that are joined together involves an increase of costs related both to the manpower necessary for the mounting and fixing, and for the production of the handle bar, for example relative to the raw material and to the molds to be made for producing two separate elements.
A further drawback lies in the fact that the use of two separate sections involves a shrinking of the space for the warehouse storage and also determines, in particular for light sections, a greater risk of damage during the step of connecting the two sections.
A further drawback lies in the fact that in order to carry out a precise adjustment of the guide chains it is necessary for the operator to have a specific training and time is necessary for installation in order to access the adjustment means inside the handle bar. In addition, such adjustment operation, also in the case of training, is attained by means of successive attempts and not in an automated manner.
A further drawback lies in the fact that following the initial mounting, during the normal use of the present blind, it is possible that the handle bar is non-aligned from the verticality condition, for example following accidental impact or unwise movements of the handle bar itself. In such cases, it is necessary for the intervention of a specialized technician, who will have to open the handle bar and newly adjust the distance between the guide chains, with a consequent increase of costs for the final user.

Presentation of the invention

In this situation, the problem underlying the present invention is to provide a fabric roller blind, which has a handle bar that can be perfectly aligned even without requiring the intervention of an operator.
A further object of the present invention is to provide a fabric roller blind, which has a handle bar that is simple and inexpensive to attain.
Another object of the present invention is to provide a fabric roller blind, which is capable of simply and easily recovering the aforesaid alignment even following impact or incorrect movements.
Another object of the present invention is to provide a fabric roller blind, which is entirely reliable in operation, and in particular capable of ensuring the aforesaid alignment even after a prolonged use over the years, without requiring a periodic maintenance.
Another object of the present invention is to provide a fabric roller blind, which is structurally simple and inexpensive to attain and install.

Brief description of the drawings

The technical characteristics of the invention, according to the aforesaid objects, can be clearly seen in the contents of the below-reported claims and the advantages thereof will be more evident in the following detailed description, made with reference to the enclosed drawings, which represent a merely exemplifying and non-limiting embodiment of the invention, in which:

figure 1 shows a front view of the fabric roller blind, object of the present invention, with a handle bar in intermediate position between an open position and a closed position;
figure 2 shows the front view of the fabric roller blind of figure 1 with several characteristics transparent in order to better illustrate other characteristics;
figure 3 shows a perspective view of a detail of the blind illustrated in figure 1, relative to synchronization chains and adjustment means;
figure 4 shows a detail in perspective view of the fabric roller blind, object of the present invention, relative to the adjustment means of figure 3, in an exploded view.

Detailed description of a preferred embodiment

With reference to the enclosed drawings, reference number 1 overall indicates the fabric roller blind, object of the present invention.
The fabric roller blind 1 is operatively employable for adjustably closing an opening A of a door/window/shutter, for example of a window, or a door or of a French window, made in a structure such as for example the building wall of a building.
In accordance with the invention the fabric roller blind 1, object of the present invention, comprises a support frame 2 intended to be fixed at an opening A of a building. The latter is for example usually defined at least between two lateral walls, one upper wall and one lower wall of the structure of the building.
Advantageously, the support structure 2 comprises a lateral upright 21 and at least one lateral abutment element 22, opposite the lateral upright 21, which substantially define the flanks of the support structure 2 of the fabric roller blind 1 and are susceptible of being fixed to the aforesaid lateral walls defining the opening A of the building. Preferably, the lateral upright 21 of the support structure 2 comprises, or directly defines, a rolling shutter box 20 intended to be positioned laterally with respect to the opening A to be screened.
Advantageously, the rolling shutter box 20 is a hollow tubular section, in particular obtained with an aluminum extrusion, which is extended with substantially vertical axis between two opposite upper and lower ends.
Advantageously, the lateral abutment element 22 is part of the support structure 2 and is preferably a U-shaped section, so as to internally delimit a cavity. Alternatively, the aforesaid lateral abutment element 22 can be a tubular element, with circular or polygonal section, internally hollow, e.g. obtained by means of folding operations. In particular, the lateral abutment element 22 is preferably obtained with an aluminum extrusion, which is extended parallel to the lateral upright 21 with substantially vertical axis between two opposite upper and lower ends.
Of course, the abutment element 22, can nevertheless also be obtained as a separate element, not constituting part of the support structure 2 and for example constituted by the internal wall of the load-bearing structure of the building which defines the opening A for the blind.
Advantageously, moreover, the support structure 2 comprises an upper guide 23, which is preferably extended between the lateral upright 21 and the abutment element 22, to which it is preferably mechanically connected, and it is advantageously fixed to the upper wall defining the opening A of the building.
Preferably the support structure 2 comprises a lower guide 24, which is extended preferably between the lateral upright 21 and the abutment element 22, to which it is preferably mechanically connected, and is advantageously fixed to the lower wall defining the opening A of the building i.e. to the ground.
Of course, without departing from the protective scope of the present invention, the support structure 2 can lack the lower guide 24, also known as "ground guide", in order to allow an improved accessibility through the blind 1.
Advantageously, the blind 1 also comprises a take-up roller, having a substantially vertical rotation axis X and rotatably constrained to the lateral upright 21 of the support frame 2 and preferably housed within the rolling shutter box 20.
Advantageously, the blind 1 also comprises a sheet 4, which has shape, once extended, preferably rectangular and is extended between a first lateral edge 4' thereof fixed to the take-up roller and a second lateral edge 4" thereof opposite the first lateral edge 4'. Preferably, the sheet 4 wound around the take-up roller passes through a vertical slit which is obtained on a lateral wall of the rolling shutter box 20 which is directed towards the opening A.
The sheet 4 can be intended for attaining a darkening screen, e.g. in substitution of a roller shutter, of a brise soleil screen for filtering sunlight or for making a mosquito netting. Generally, the sheet 4 can be dedicated to closing the opening of a door/window/shutter in order to protect an internal area from the sun and/or from the wind and/or, more generally, from the atmospheric conditions of the outside environment.
In accordance with the invention, the fabric roller blind 1 also comprises a handle bar 5, slidably associated with the support frame 2, preferably between the lateral upright 21 and the lateral abutmemt 22. The handle bar 5 is extended along an extension axis Z between a lower termination 5', preferably connected to the lower guide 24, and an upper termination 5", preferably connected to the upper guide 23, and is provided with an axial cavity 50.
Advantageously, the handle bar 5 is attained with a hollow tubular body, in particular obtained with an aluminum extrusion which is preferably made in a single body, and the aforesaid axial cavity 50 is defined inside the aforesaid hollow tubular section. Advantageously, the handle bar 5 is fixed to the second lateral edge 4" of the sheet 4, in order to allow the unwinding of the sheet 4 from the take-up roller in order to selectively arrange it to cover and open the opening A.
More in detail, the handle bar 5 is advantageously movable between an open position, in which it is placed at the take-up roller, and in particular it is placed in abutment against the rolling shutter box 20, freeing the opening A from the sheet 4, and a closed position, in which the handle bar 5 is placed in distal position with respect to the take-up roller, preferably in abutment against the lateral abutment element 22, with the sheet 4 which is placed to cover the opening A.
The fabric roller blind 1 also comprises at least two synchronization chains 6, 7, mechanically connected to the support frame 2 and mechanically connected to each other.
The synchronization chains 6, 7 are subjected to a tensioning force Ft and are adapted to synchronize the advancement of the terminations 5', 5" of the handle bar 5 during its movement. In particular, the synchronization chains 6, 7 advantageously allow moving the handle bar 5, maintaining the terminations 5', 5" thereof substantially aligned along the extension axis Z and hence maintaining the handle bar 5 in a substantially vertical position.
More in detail, with the expression "tensioning force" it will be intended hereinbelow the resultant of the forces acting on a point of connection between the two synchronization chains 6, 7. In particular, such tensioning force Ft, during the normal use of the blind 1, is preferably ascribable substantially to only the weight force of one portion of the synchronization chain connected to the lateral upright 21 which is housed within the axial cavity 50 of the handle bar 5.
The synchronization chains 6, 7 comprise a first synchronization chain 6, provided with a first internal end 6A housed inside the handle bar 5, and in particular in the axial cavity 50, and slidable within this.
Advantageously, the first synchronization chain 6 is also provided with a first external end 6B, which is connected to the support frame 2, preferably to the lateral abutment element 22, or to the upper margin of the section that forms such lateral abutment element 22.
Advantageously, the first synchronization chain 6 is therefore susceptible of being extended above the opening A of the load-bearing structure of the building.
The synchronization chains 6, 7 also comprise a second synchronization chain 7, provided with a second internal end 7A, mechanically connected to the first internal end 6A of the first synchronization chain 6, housed inside the handle bar 5, and in particular to the axial cavity 50, and slidable within this.
Advantageously, the second synchronization chain 7 is provided with a second external end 7B, connected to the support frame 2, preferably to the base 21A of the lateral upright 21.
Advantageously, the second synchronization chain 7 is therefore susceptible of being extended below the opening A of the load-bearing structure of the building.
As can be appreciated from the enclosed figures, the first synchronization chain 6 enters the handle bar 5, being bent downward, i.e. defining a first concavity directed towards the lateral abutment element 22. In turn, the second synchronization chain 7 enters the handle bar 5, being bent upward, with a second concavity directed towards the lateral upright 21.
Advantageously, the two synchronization chains 6, 7 define, at any one intermediate position of the handle bar 5, an S-shaped progression mirrored with respect to an axis passing through the handle bar 5, as can be appreciated in figure 1.
Of course, without departing from the protective scope of the present patent, such S-shaped mirrored progression can, in an entirely equivalent manner, be S-shaped (non-mirrored) with the first external end 7B of the second synchronization chain 7 connected to the upper end of the lateral upright 21 and with the second internal end 7A of the second synchronization chain 7 connected to the lateral abutment element 22 at the base of the support frame 2. In this case the first concavity will be directed towards the lateral upright 21 instead of towards the lateral abutment element 22 and the second concavity will be directed towards the lateral abutment element 22.
The fabric roller blind 1 also comprises adjustment means 8, which are placed within the handle bar 5 (within the axial cavity 50) and comprise a first adjustment body 9, connected to the first synchronization chain 6, preferably at the first internal end 6A, and a second adjustment body 10, connected to the second synchronization chain 7, preferably to the second internal end 7A, and to the first adjustment body 9.
Advantageously, the adjustment bodies 9, 10 are made of a polymer material and are rigidly fixed to the synchronization chains 6, 7 and the tensioning force Ft is distributed thereon such that the two adjustment bodies 9, 10 are moved away or close by the aforesaid tensioning force Ft.
In accordance with the idea underlying the present invention, the second adjustment body 10 comprises at least one longitudinal guide 12, substantially parallel to the extension axis Z and along which the first adjustment body 9 is slidably free to be moved. In this manner the first adjustment body 9 and the second adjustment body 10 are slidably and guidedly engaged, in order to move the first internal end 6A and the second internal end 7A close to or away from each other.
In addition, at least one between the first adjustment body 9 and the second adjustment body 10 comprises at least one first pressure element 11, which is susceptible of exerting a friction force Fa between the first adjustment body 9 and the second adjustment body 10, retaining the first adjustment body 9 constrained in an operative position along the longitudinal guide 12, with tensioning forces Ft between the synchronization chains 6, 7 lower than the friction force Fa.
More in detail, with the expression "operative position" it will be intended hereinbelow the mutual position between the adjustment bodies 9, 10 (and consequently a mutual position between the synchronization chains 6, 7) which allows positioning the handle bar 5 substantially vertical, with the two terminations 5', 5" aligned along the extension direction Z.
In this manner it is therefore possible to retain the handle bar 5 in the aforesaid vertical position during the normal use of the fabric roller blind, since the forces at play exchanged between the two synchronization chains 6, 7 (equivalent to the tensioning force Ft) are smaller than the friction force Fa and do not allow the mutual sliding of the two adjustment bodies 9, 10.
In this manner, moreover, in case of misalignments of the handle bar 5 (for example due to impact or incorrect movements of the handle bar 5), it is possible to easily realign the handle bar 5, adjusting the distance between the two adjustment bodies 9, 10.
More in detail, it is possible to vary the relative distance between the first ends 6A, 7A of the two synchronization chains 6, 7 by means of the application of an external force Fe greater than the friction force Fa (or which summed with the pre-existing tensioning force Ft is greater than the friction force Fa), in order to induce the mutual sliding of the adjustment bodies 9, 10.
In operation, it is therefore advantageously possible first of all to induce the relative sliding of the first adjustment body 9 along the second adjustment body 10, by applying an external force Fe greater than the friction force Fa, and subsequently constrain the two adjustment bodies 9, 10 (and the two synchronization chains 6, 7) into the operative position, terminating the application of the external adjustment force Fe upon reaching the desired operative position.
In operation, the above-described adjustment is for example attainable by acting on one of the two terminations 5', 5" of the handle bar 5 in order to align it with the other termination, or alternatively by bringing the handle bar 5 in abutment against the lateral abutment 22 (or the lateral upright 21) in order to force the alignment of the handle bar 5.
In accordance with the preferred embodiment, illustrated in the enclosed figures, the first adjustment body 9 has elongated shape and is extended along an extension axis substantially parallel to the extension direction Z, between a first upper end 9', preferably connected to the first internal end 6A of the first synchronization chain 6, and a first lower end 9", connected to the second adjustment body 10.
Advantageously the first synchronization chain 6 is provided with at least one engagement hole, which is preferably made at the first internal end 6A, in particular at the last element of the carriage that constitutes the synchronization chain 6.
Advantageously, the first adjustment body 9 is provided with first coupling means 91, made at the first upper end 9'. Preferably, the first coupling means 91 comprise at least one pin 910, which engages the aforesaid engagement hole made on the first internal end 6A of the first synchronization chain 6.
Advantageously, the second adjustment body 10 has elongated shape and is extended along an extension axis substantially parallel to the extension direction Z, between a second lower end 10", preferably connected to the second internal end 7A of the second synchronization chain 7, and a second upper end 10', preferably connected to the first upper end 9' of the first adjustment body 9.
Advantageously, the second adjustment body 10 is provided with second coupling means (not represented), preferably made at the second lower end 10". Preferably, the second coupling means comprise two holes, made laterally with respect to the second adjustment body 10, transverse with respect to the extension direction Z, which are engaged by corresponding pins obtained on the second internal end 7A of the second synchronization chain 7.
Of course, without departing from the protective scope of the present invention, the first adjustment body 9 and the second adjustment body 10 are made in a single body respectively with the first synchronization chain 6 and with the second synchronization chain 7.
Preferably the first adjustment body 9 has substantially prismatic shape and is extended, orthogonal to the extension direction Z, between a first wall 91, directed towards the second adjustment body 10, and a second wall 92, opposite the first wall 91, preferably parallel to the first wall 91 and preferably parallel to the extension direction Z.
Preferably the second adjustment body 10 has substantially prismatic shape and is extended, orthogonal to the extension direction Z, between a third wall 103, directed towards the first adjustment body 9, and a fourth wall 104, opposite the third wall 103, which are preferably substantially parallel to each other and to the extension direction Z. The first wall 91 of the first adjustment body 9 and the third wall 103 of the second adjustment body 10 are facing and placed substantially parallel.
Advantageously, the first adjustment body 9 is provided with at least one first friction surface 90 and the second adjustment body 10 is provided with a second friction surface 100. Preferably, the first and the second friction surface 90, 100 are substantially planar and parallel, in order to allow a linear mutual sliding of the first adjustment body 9 and of the second adjustment body 10.
Advantageously, the first wall 91 of the first adjustment body 9 and the third wall 103 of the second adjustment body 10 at least partially define the first friction surface 90 and the second friction surface 100.
Advantageously, the first adjustment body 9 is slidably engaged in the longitudinal guide 12 with a transverse clearance G, oriented along a direction substantially orthogonal to the extension axis Z of the handle bar 5.
More in detail, the transverse clearance G is to be intended as a clearance that is present in the event in which the first adjustment body 9 and the second adjustment body 10 are released, without any force that pushes them in abutment against each other.
The clearance G is for example due to the normal tolerances of the production processes used for attaining the adjustment bodies 9, 10. Otherwise, the clearance G is due to the wear caused by the friction between the first and the second adjustment body 9, 10, and can be increased during the normal use of the fabric roller blind 1, in particular after a high number of opening/closing cycles of the handle bar 5.
The action of the first pressure element 11 constantly overcomes the aforesaid clearance G and carries the first friction surface 90 of the first adjustment body 9 in contact with the second friction surface 100 of the second adjustment body 10 in order to retain, connected in abutment, the first adjustment body 9 and the second adjustment body 10. Therefore the transverse clearance G is advantageously absent during the normal use of the fabric roller blind 1 due to the continuous transverse force exerted by the pressure element 11.
In this manner the pressure element 11 therefore advantageously allows constantly recovering, during the normal use of the fabric roller blind 1, the clearance G generated between the two adjustment bodies 9, 10 and allows the adjustment means 8 to be self-adapted in order to maintain the two friction surfaces 90, 100 constantly in abutment and prevent the moving apart of the adjustment bodies 9, 10.
Advantageously, the second adjustment body 10 comprises a concavity and the longitudinal guide 12 comprises a guide channel 120, defined by the aforesaid concavity.
More in detail, the guide channel 120 has substantially C-shaped form and is preferably delimited by three walls connected to each other, including a bottom wall, preferably coinciding with the third wall 103, and two lateral walls, projecting from the aforesaid bottom wall.
Advantageously, the first adjustment body 9 is at least partially housed in the guide channel 120 in order to slide guidedly along the latter.
Preferably, the second adjustment body 10 is provided with an upper opening, made at the second upper end 10' of the second adjustment body 10. The aforesaid upper opening is arranged for slidably housing the first adjustment body 9 such that the latter is substantially aligned with the second adjustment body 10.
Advantageously, one between the first adjustment body 9 and the second adjustment body 10 comprises at least one first stop portion 14, and the other comprises at least one first abutment portion 15 adapted to abut against the first stop portion 14 in order to stop the mutual sliding of the adjustment bodies 9, 10.
In accordance with the preferred embodiment, illustrated in the enclosed figures, the second adjustment body 10 comprises two first stop portions 14, which are made on the third wall 103 of the second adjustment body 10, projecting from the latter and substantially orthogonal to the extension direction Z. Advantageously, each first stop portion 14 comprises two walls 140, which are preferably made by opposite edges of the third wall 103 of the second adjustment body 10 and at least partially delimit, with the aforesaid third wall 103, the guide channel 120.
In accordance with the aforesaid embodiment, the first adjustment body 9 comprises a first abutment portion 15, which is made on the second wall 92 of the first adjustment body 9.
More in detail, the first abutment portion 15 comprises a bracket 150 transverse to the extension direction Z, which is made in proximity to the first lower end 9" of the first adjustment body 9 and is extended for an extension greater than the width of the first adjustment body 9 along a direction orthogonal to the extension direction Z. Advantageously, the first abutment portion 15 is placed outside the guide channel 120, preferably in abutment against the walls 140 of the first stop portion 14, in order to define a guide surface with the latter.
In this manner, during the mutual sliding of the two adjustment bodies 9, 10, the first abutment portion 15 guides the first adjustment body 9 along the longitudinal guide 12. In addition, the first abutment portion 15 prevents the lateral exit of the adjustment body 9 from the guide channel 120, abutting against the first stop portions 14.
Advantageously, one between the first adjustment body 9 and the second adjustment body 10 comprises at least one second stop portion 16, and the other comprises at least one second abutment portion 17 adapted to abut against the second stop portion 16 in order to prevent the mutual moving apart of the adjustment bodies 9, 10, along a direction substantially orthogonal to the extension axis Z.
Advantageously the second stop portion 16 is made on the second adjustment body 10, in particular on the first stop portion 14 of the second adjustment body 10. More in detail, the second stop portion 16 preferably comprises two protrusions 160, made on the opposite walls of the first stop portion and which are extended substantially orthogonal to the extension direction Z.
In addition, the first adjustment body 9 comprises a second abutment portion 17, preferably defined by the second wall 92 of the same first adjustment body 9, on opposite sides of the second wall 92. Advantageously, the second abutment portion 17 is susceptible of sliding against the second stop portion 16, such to increase the guide surface during the sliding of the adjustment bodies 9, 10.
In addition, in this manner, the first adjustment body 9 housed within the guide channel 120 is prevent from moving away from the second adjustment body 10 (along a direction orthogonal to the extension direction Z) due to mechanical engagement between the second abutment portion 17 and the second stop portion 16.
Of course, without departing from the protective scope of the present invention, the first stop portion 14 and the second stop portion 16, with the relative first and second abutment portions 15, 17 can be shaped different from that described above, as long as the technical effect of preventing the separation of the two adjustment bodies 9, 10 is maintained along two directions that are transverse to each other and substantially orthogonal to the extension direction Z.
Advantageously, the pressure element 11 comprises at least one magnet 110, which exerts a magnetic return force Fr and retains in abutment the first adjustment body 9 and the second adjustment body 10.
More in detail, the magnet 110 is preferably selected from among a neodymium magnet, a ferrite magnet, samarium-cobalt magnet, alnico magnets or another type of magnet suitable for such purpose.
Advantageously, the other adjustment body 9, 10 (not comprising the magnet 110) comprises at least one second pressure element 13, made of a magnetic or ferromagnetic material, which is magnetically connected to the first pressure element 11 in order to retain the first adjustment body 9 and the second adjustment body 10 connected to each other.
Hereinbelow, for sake of description simplicity, reference will be made to the preferred embodiment, in which the first pressure element 11 is connected to the first adjustment body 9 and the second pressure element 13 is connected to the second adjustment body 10; nevertheless, it is possible to reverse the adjustment bodies 9, 10 to which the two pressure elements 11, 13 are connected, of course without departing from the protective scope of the present patent.
More in detail, in accordance with the preferred embodiment, illustrated in the enclosed figures, the second pressure element 13 is made of a ferromagnetic material, e.g. iron, and comprises advantageously a metallic plate 130.
Preferably, the second pressure element 13 is integral with the second adjustment body 10 by means of retention means of known type, such as for example screws, rivets or alternatively by means of the application of a glue layer.
Advantageously, the second pressure element 13 is retained in the guide channel 120 by means of fitting engagement, for example by means of one or more shoulders projecting from the second adjustment body 10 within the guide channel 120, in order to interfere with the second pressure element 13 and retain it in position.
In accordance with the aforesaid preferred embodiment the metallic plate 130 is at least partially housed within the longitudinal guide 12 of the second adjustment body 10, preferably within the guide channel 120 and is still more preferably set on a bottom wall of the guide channel 120 itself, which preferably coincides with the third wall 103 of the second adjustment body 10.
Otherwise, in accordance with an embodiment variant illustrated in the enclosed figures the second pressure element 13 is a second magnet, connected to the second adjustment body 10, for example within the guide channel 120.
Advantageously, at least one between the first pressure element 11 and the second pressure element 13 at least partially defines the first friction surface 90 or the second friction surface 100. Preferably, both the pressure elements 11, 13 define the friction surface 90, 100 and in particular the first pressure element 11 at least partially defines the first friction surface 90 of the first adjustment body 9, while the second pressure element 13 at least partially defines the second friction surface 100 of the second adjustment body 10.
In this manner the adjustment bodies 9, 10 are slidably engaged by means of the slidable engagement of the two pressure elements 11, 13.
Of course, it is also possible to connect one or both pressure elements at a rear portion of the adjustment bodies 9, 10, in particular at the second wall 92 of the first adjustment body 9 and at the fourth wall 104 of the second adjustment body 10.
In such case, the two adjustment bodies 9, 10 are advantageously made of metallic material and are therefore at least partially placed within the magnetic field generated by the two pressure elements 11, 13, hence in order to be maintained with the respective friction surfaces 90, 100 in abutment against the action of the magnetic force between the two pressure elements 11, 13.
Advantageously, at least one between the first adjustment body 9 and the second adjustment body 10 is provided with a housing seat S, adapted to at least partially house the first pressure element 11.
More in detail, the first housing seat S is counter-shaped with respect to the first pressure element 11 in order to receive it substantially to size.
Advantageously, the first housing seat S is extended in depression from the first wall 91 of the first adjustment body 9, up to a bottom wall thereof, hence preferably being blind. Advantageously, the first pressure element 11 is disc-shaped, and is extended between a first external face 11', directed towards the second adjustment body 10, and a first internal face 11", opposite the first external face 11'.
Preferably, the housing seat S is provided with a depth (measured along a direction substantially orthogonal to the extension direction Z) which is substantially equal to the depth of the first pressure element 11.
In this manner the first external face 11' of the first pressure element 11 is substantially coplanar, preferably continuously, with the first wall 91 of the first adjustment body 9. Advantageously, the first adjustment body 9 is provided, on its second wall 92, with a fixing portion 93, which is extended projecting from the second wall 92 and is provided with a threaded hole, placed in communication with the housing seat S. Advantageously, the first pressure element 11 is provided with a hole, preferably through, which is aligned with the threaded hole of the fixing portion 93 when the pressure element 11 is housed within the first housing seat S, so as to connect the first pressure element 11 and the first adjustment body 9 by means of for example a screw placed to traverse the aforesaid through hole and the threaded hole made in the fixing portion 93 of the first adjustment body 9.
Of course, without departing from the protective scope of the present invention, the first pressure element 11 can be otherwise connected to the first adjustment body 9, by means of connection means that are well-known to the man skilled in the art and therefore not described in detail hereinbelow.
In accordance with an embodiment variant, not illustrated in the enclosed figures, the first pressure element 11 comprises at least one spring (not represented), which exerts an elastic return force Fr, is placed as a mechanical connection between the adjustment bodies 9, 10 and retains them in abutment.
Advantageously, the spring of the first pressure element 11 is placed as a mechanical connection (directly or indirectly) between the first and the second adjustment body 9, 10.
For example, it is possible to connect the spring to the adjustment bodies 9, 10 indirectly, by interposing two thrust plates, each of which connected to an adjustment body 9, 10.
In such case, the spring of the pressure element 11 is extended between a first end, which is fixed to an adjustment body 9, 10 (directly or indirectly) and a second end, which is connected to an element that is slidable with respect to the other adjustment body 9, 10, in order to allow the sliding of the spring of the pressure element 11 also during the mutual sliding of the adjustment bodies 9, 10.
Advantageously, the pressure element 11 comprises two springs, which are connected to the adjustment bodies 9, 10 as described above, preferably from opposite sides with respect to the aforesaid adjustment bodies 9, 10.
Advantageously, the first friction surface 90 and the second friction surface 100 are respectively provided at least with a first roughness R1 and at least with a second roughness R2, which define a static friction coefficient µs between the first friction surface 90 and the second friction surface 100, and the friction force Fa is generated between the first friction surface 90 of the first adjustment body 9 and between the second friction surface 100 of the second adjustment body 10 and is equal to the product between the return force Fr, exerted by the first pressure element 11, and the static friction coefficient µs and is preferably greater than 20 N.
In this manner it is possible to vary as desired the roughness of the friction surfaces 90, 100 or alternatively the return force Fr exerted by the first pressure element 11 so as to reach the desired friction force Fa.
The fabric roller blind 1 and its operating method thus conceived therefore attain the pre-established objects.

Claims

Fabric roller blind, which comprises:
- a support frame (2), intended to be fixed at an opening (A) of a building;

- a handle bar (5), slidably associated with said support frame (2), provided with an axial cavity (50) and extended along an extension axis (Z) between a lower termination (5') and an upper termination (5");

- at least two synchronization chains (6, 7), connected to said support frame (2), mechanically connected to each other, subjected to a tensioning force (Ft) and adapted to synchronize the advancement of the terminations (5', 5") of said handle bar (5) during its movement, including:
- a first synchronization chain (6), provided with a first internal end (6A) housed inside said handle bar (5) and slidable within this;

- a second synchronization chain (7), provided with a second internal end (7A), mechanically connected to the first internal end (6A) of said first synchronization chain (6), housed inside said handle bar (5) and slidable within this;

- adjustment means (8), placed within said handle bar (5), comprising a first adjustment body (9), connected to said first synchronization chain (6) and a second adjustment body (10), connected to said second synchronization chain (7) and to said first adjustment body (9);
the fabric roller blind (1) is characterized in that said second adjustment body (10) comprises at least one longitudinal guide (12), substantially parallel to said extension axis (Z), and said first adjustment body (9) is slidably free to be moved along said longitudinal guide (12) and that at least one between said first adjustment body (9) and said second adjustment body (10) comprises at least one first pressure element (11), which is susceptible of exerting a friction force (Fa) between said first adjustment body (9) and said second adjustment body (10), retaining said first adjustment body (9) constrained in an operative position along said longitudinal guide (12), with tensioning forces (Ft) between said synchronization chains (6, 7) lower than said friction force (Fa).
Fabric roller blind according to claim 1, characterized in that said first adjustment body (9) is provided with at least one first friction surface (90) and said second adjustment body (10) is provided with a second friction surface (100), said first adjustment body (9) is slidably engaged in said longitudinal guide (12) with a transverse clearance (G), oriented along a direction substantially orthogonal to said extension axis (Z) and the action of the first pressure element (11) constantly overcomes said clearance and carries the first friction surface (90) of said first adjustment body (9) in contact with the second friction surface (100) of said second adjustment body (10) in order to retain, connected in abutment, said first adjustment body (9) and said second adjustment body (10).
Fabric roller blind according to claim 1 or 2, characterized in that said pressure element (11) comprises at least one magnet, which exerts a magnetic return force (Fr) and retains in abutment said first adjustment body (9) and said second adjustment body (10), and that the other adjustment body (9, 10) comprises at least one second pressure element (13), made of a magnetic or ferromagnetic material, which is magnetically connected to said first pressure element (11) in order to retain, connected to each other, said first adjustment body (9) and said second adjustment body (10).
Fabric roller blind according to claim 3, characterized in that said first pressure element (11) and said second pressure element (13) at least partially define, respectively, said first friction surface (90) and said second friction surface (100).
Fabric roller blind according to claim 3 or 4 characterized in that at least one between said first adjustment body (9) and said second adjustment body (10) is provided with a first housing seat (S), adapted to at least partially house said first pressure element (11).
Fabric roller blind according to claim 1 or 2, characterized in that said first pressure element (11) comprises at least one spring, which exerts an elastic return force (Fr), is placed to mechanically connect said first adjustment body (9) and said second adjustment body (10) in order to retain them in abutment against each other.
Fabric roller blind according to any one of the claims from 3 to 6, characterized in that said first friction surface (90) and said second friction surface (100) are respectively provided at least with a first roughness (R1) and at least with a second roughness (R2), and define a static friction coefficient (µs) between said first friction surface (90) and said second friction surface (100);
said friction force (Fa) being developed between said first friction surface (90) of said first adjustment body (9) and between said second friction surface (100) of said second adjustment body (10) and being equal to the product between said return force (Fr), exerted by said first pressure element (11), and said static friction coefficient (µs) and being greater than 20N.
Fabric roller blind according to any one of the preceding claims, characterized in that said second adjustment body (10) comprises a concavity and said longitudinal guide (12) comprises a guide channel (120), which is defined by said concavity; said first adjustment body (9) being at least partially housed in said guide channel (120) in order to slide guidedly along said guide channel (120).
Fabric roller blind according to any one of the preceding claims, characterized in that one between said first adjustment body (9) and said second adjustment body (10) comprises at least one first stop portion (14), and that the other between said first adjustment body (9) and said second adjustment body (10) comprises at least one first abutment portion (15) adapted to abut against said first stop portion (14) in order to stop the mutual sliding of said adjustment bodies (9, 10).
Fabric roller blind according to any one of the preceding claims, characterized in that one between said first adjustment body (9) and said second adjustment body (10) comprises at least one second stop portion (16), and that the other between said first adjustment body (9) and said second adjustment body (10) comprises at least one second abutment portion (17) adapted to abut against said second stop portion (14) in order to prevent the mutual moving apart of said adjustment bodies (9, 10), along a direction substantially orthogonal to said extension axis (Z).