ES2650788T3 - A compensation system for pleated screens, such as mosquito nets and blinds - Google Patents

Abstract

A compensation system for screens for window or door openings, such as, for example, mosquito nets and blinds, comprising at least one pleated sheet (2) inserted in a perimeter structure that can be fixed on at least two sides opposite the opening to be hidden, said system comprising elements for the connection of the corners of the perimeter structure of the screen, that is, for the connection of the ends of the elements in guide section (10, 18) and of the elements in vertical section (15, 17) of the structure, said system being characterized in that said connecting elements are designed to provide a rigid perimeter frame constituted by said fixed vertical section elements (15, 17) and said elements in guide section (10, 18) within which the pleated screen (2) is stretched / compressed by moving at least one element in mobile section or "handle" (16); in addition, an additional section element (11) is provided, which is fixed to the opening in which the screen is installed and is designed to cooperate with at least one of the elements in guide section (10) - by means of a telescopic coupling in a direction substantially transverse to the guide section element itself - to compensate for the dimensional differences between said perimeter structure containing the sheet (2) and the opening in which it is installed; in which all the elements in section of the structure have one and the same transversal dimension with respect to the plane of the screen itself.

Description

DESCRIPTION

A compensation system for pleated screens, such as mosquito nets and blinds

[0001] The present invention relates to the sector of accessories for doors and windows, and in particular to the

installation of pleated type screens.

[0002] The main objective of a screen is notoriously to prevent light (in the case of blinds) or insects (in the case of mosquito nets) from entering the internal environments of offices or homes from

10 openings of doors or windows in the walls.

[0003] Technical solutions are known in the art in which, for convenience, the above screens can be temporarily removed from the corresponding opening by sliding or rotation (obtained by manual or motor drive) of one or more screen elements.

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[0004] For example, from US No. 2007/267152 a system for window or door opening screens is known which comprises at least one pleated sheet and a rigid perimeter structure with connecting elements at the corners of said structure, which consists of vertical sectional elements and guide sectional elements 1, as well as a mobile sectional element.

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[0005] An aspect of these devices that is of increasing importance is represented by their integration with the other structural elements of the opening (mainly the accessories for doors and windows) both from the dimensional point of view and from the aesthetic point of view. The ideal product has small overall dimensions and uniform size across the perimeter and has an aspect that can be combined

25 easily with the other elements present in the opening.

[0006] Using as a classification criterion the type of system used for temporary removal (or deactivation) of the screen, three types of screens can be identified: folding screens, rolling screens and pleated screens.

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[0007] Folding screens allow the opening or a portion thereof to be discovered causing sliding or rotation of the screen panels that form them.

[0008] The rolling screens provide, instead, the winding of the screen around a cylindrical element (or drum) generally contained in a box.

[0009] Finally, the pleated screens provide for the use of a screen equipped with a series of parallel folds equally separated from each other and at close range. By compressing the folds, it is possible to compact the screen and contain it within a space corresponding to the distance between one fold and the next.

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[0010] The classification presented above reflects the chronological order in which the various types appeared, that is, the technical evolution of the screens.

[0011] Folding screens are characterized by their robustness and simplicity, but they are not particularly attractive since the panel always remains completely visible. They also require, in the case of

rotation drive, free space in the opening direction.

[0012] Rolling screens exceed the folding limit of the screens since the sheet is wound around a cylindrical element (called "drum") that is hidden within a box element. The side of the

The screen opposite the fixed one with respect to the drum is attached along its entire length to a sliding sectional element, the movement of which allows the sheet to be wound and unwound, while the other two sides of the screen are housed within two lateral guides.

[0013] This solution implies that, if the objective is, of course, to prevent the screen from curling around a drum diameter that is too small (which would create winding problems), the box that houses both

Elements may not contain dimensions very well. In effect, the box constitutes a hindrance in the transverse direction that is much larger than that of the other elements of the described structure.

[0014] This makes it difficult to give this type of screen an appearance that is uniform throughout its

perimeter, linear and orderly.

[0015] From the point of view of integration with the elements of the openings, the pleated screens allow to obtain the best result, since the transverse dimension is linked to the width of the screen

5 compressed (and this, in turn, is related to the distance between the folds), and the structural elements of the screen can be very similar to each other and uniform.

[0016] The typical composition of screens of the latter type provides at least one quadrilateral pleated sheet comprised between two elements in section (parallel to the folds of the screen) of which at least one is

10 mobile and can be used, according to the user's requirements, to open (activate) or compress (deactivate) the screen.

[0017] With regard to the other two sides of the screen, the sheet is contained by sectional elements called "lateral guides".

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[0018] The lateral guides have the double function of guiding the sliding of the element (or elements) in mobile section and of accommodating in them the lateral edges of the sheet, guaranteeing the complete closing of the opening, which is a necessary feature for proper operation of the screen.

[0019] The elements in section fixed to which are the two sides of the screen and which are parallel to

The folds thereof are generally shaped to contain the screen when it is compressed to protect and hide it from view.

[0020] From this it follows that the cross-sectional dimensions of said sectional elements are equal to 25 the transverse dimension of the compressed sheet (ie, the folding distance) plus twice the thickness of the

walls of the sectional elements that contain the sheet.

[0021] The pleated screens currently available also offer the possibility of compensating for possible errors or approximations related to the dimensions of the opening. In fact, it may happen that the

30 screen dimensions are, for various reasons, slightly different from those of the opening. In the opening direction, the pleated screen makes it possible to cover an opening larger than expected, simply by stretching the folds to a greater extent. In the direction perpendicular to the opening direction, the width is compensated by the conformation of the lateral guides that house inside them the end of the elements in section of the screen and that allow a greater or lesser interpenetration according to the difference between the size of the opening and 35 of the screen.

[0022] In general, at least one of the two lateral guides houses the ends of the elements in section parallel to the folds of the screen, so that, for this guide, it is possible to obtain a transverse dimension equal to that of the element in section plus twice the wall thickness of the guide itself.

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[0023] It can be easily understood, from a constructive point of view, that for this type of product the main transverse dimension of the screen (ie that of the lateral guides) is determined almost automatically once the width has been chosen of the fold, since the minimum thickness of the walls is a constructive characteristic that varies only to a lesser extent within the framework of the technologies used for this

45 type of applications.

[0024] By reducing the space between the folds of the screen, it is obviously possible to reduce the cross-sectional dimension of the structure, but there is an aspect that makes spacing that is too narrow unusable.

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[0025] Given the same dimensions of a screen, the smaller the space between the folds, the greater the number of folds, with an increase in the dimensions of the compressed screen: in this case, to keep the sheet hidden between the elements in section, it is necessary to modify the latter and increase the cavity used to house the compressed screen. The result would be wide sectional elements and

55 unsightly.

[0026] Therefore, there is a need to reach a compromise between the number of folds and the distance between them, and in fact the screens currently existing mostly employ fold distances that never depart from a range of rather narrow values.

[0027] If, on the one hand, the possibility of reducing the dimensions in a direction transverse to the plane of the screen meets the technological limits as described above, on the other hand, the contained dimensions would allow the installation of the screen even in areas where there is little space available: have a

5 screen that is even a bit thinner can represent a great advantage over the products currently available in the market.

[0028] In accordance with the known technique, the pleated sheet is received within shaped sectional elements to receive it within them when compressed. These sectional elements must have a

10 transversal dimension greater than that of the sheet they receive. Said sectional elements slide inside the lateral guides and, therefore, the latter have a size that is larger than said sectional elements. This configuration offers the advantage that the screen is self-compensating, that is, it can be adapted to the opening even in the case of dimensional imperfections, but it implies different cross-sectional dimensions for the sectional elements previously described.

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[0029] The invention presented herein allows the reduction of the transverse dimension of the screen advantageously without changing the transverse dimension of the compressed sheet. Basically, the inventive idea underlying the invention consists of a particular connection of the corners of the perimeter structure of the screen, namely, the connection between the element (or elements) in the guide section and the

20 elements in vertical section of the structure.

[0030] It should be appreciated that in the figures attached hereto by way of example, the screen is stretched or compressed laterally, and therefore, the elements in guide section are horizontal (upper and lower) and the elements in vertical section they are vertical (right and left), but the invention works without any

25 modification also in the case of installation with the screen that is stretched or compressed in a vertical direction.

[0031] The present invention avoids the need for dimensional differences between the elements in section containing the sheet and the elements in guide section without sacrificing the possibility of being able to compensate

30 easily possible dimensional differences between the screen and the opening in which it is installed. In fact, all the elements of the screen have the same transversal dimension, and therefore, an aesthetic improvement of the same is also achieved.

[0032] A further advantage of the invention to be described is represented by the fact that, while in the currently known solutions, the greater the difference to be compensated (ie an opening

larger than expected at the time of screen production), smaller is the portion of the sheet that is mounted on the guide (or guides), in the present invention, the sheet does not come out at any point of the guide even when it is it is necessary to compensate for a certain dimensional difference between the screen and the opening that houses it.

[0033] Other features and advantages of the invention will be better understood with reference to the following

detailed description and attached drawings with respect to a preferred, but not exclusive, embodiment of the pleated screen according to the invention, illustrated by way of indication. and non-limiting example, in which:

- Figures 1 and 2 illustrate the composition of the screen 1 forming the object of the invention; it is possible to recognize the pleated sheet 2 contained between the elements in section 15 and 16 and the lateral guide elements 10 and 18;

- Figures 3 and 4 illustrate the elements that form one of the corners of the structure and, in particular, the elements that provide the connection between the elements in section;

- Figure 5 illustrates the particular connection system between the element in section 15 (or 17) and the final element 9 (or

14);

50 - Figure 6 illustrates in detail a corner of the screen;

- Figures 7, 8 and 9 illustrate the sequence of operations corresponding to the assembly of one of the corners of the screen structure: and

- Figure 10 represents an example of the known technique.

[0034] With reference to the figures listed above, screen 1 is particularly suitable

to prevent light (in the case of blinds) or insects (in the case of mosquito nets) from entering the internal environments of offices or homes from openings in the walls, such as windows, doors and the like.

[0035] Screen 1 comprises at least one pleated sheet 2 preferably manufactured (but not

exclusively) of polymeric material mounted on a substantially perimeter structure that in turn is fixed to hide at least on two opposite sides.

[0036] The structure is formed perimetrically by two elements in section 15 and 17 parallel to the

pleated, which can be fixed to the opening in which the screen is installed, of which at least one element in section, 15, is connected to one side of the pleated sheet 2 and two other elements in section, 10 and 18, orthogonal at first, they have a guide function for the own sheet. Within said structure there is at least one element in mobile section 16, parallel to said elements in section 15 and 17 that are parallel to the fold, which can be freely slid with its ends in the elements (or guides) in guide section 10 and 18. Said the element in movable section 16 is connected to the pleated sheet 2, on the opposite side from that connected to the element in section 15.

[0037] According to a known operating mode, the screen can assume two configurations:

15 - activated screen, that is, pleated sheet 2 stretched and hiding the entire area of the opening;

- screen off, ie pleated sheet 2 compressed, and opening without screen.

[0038] To move from one configuration to the other, it is sufficient to grab the element in mobile section 16 and make it slide (for this reason, said element 16 is called "handle"). The screen is activated when the

20 element in mobile section 16 rests against the element in section 17 (the element in section 17 is commonly referred to as "element in closing section") and the sheet extends from one part to the other of the structure. By causing the handle 16 to slide in an opposite direction until it rests against the element in section 15, the sheet 2 is compressed and the opening is consequently free.

[0039] At the upper and lower ends of each of the elements in section 15, 16 and 17,

commonly found accessories called "end elements" or "plugs" designated, respectively, by 9 and 19, 13 and 20, 14 and 21. The function of said components is to close the ends of the elements in section and, in some known solutions , together with components 8 and 22 (fixed at the ends of the elements in guide section 10 and 18), allow the fixing of the elements in section at the opening.

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[0040] According to the known technique, the installation contemplates the following stages:

- fix the elements in guide section (10 and 18) to the opening surfaces by means of fixing screws; Y

- fit the element in section 17 and the element in section 15 into the guides and then fix it to the opening by means of quick-action locking in the accessories 23 previously fixed to the opening or even

by means of the interlocking element between the final elements at the ends of said sectional elements and accessories established at the ends of the guides.

[0041] According to the known technique, as already described, the transverse dimensions of the 40 elements in guide section 10 and 18 are larger than those of the elements in section 15, 16 and 17 to allow

adjustment of the last in the guides.

[0042] Unlike the known technique, the present invention provides that:

45 - the elements in guide section 10 and 18 and the elements in section 15, 16 and 17 perpendicular thereto have the same dimension in a direction transverse to the plane of the screen to minimize the transverse dimension of the structure and improve the appearance Of the same;

- the final elements 9, 13 and 14 are shaped so that the part to be received in the guide 10 has a reduced transverse dimension very close to the transverse dimension of the sheet: only the part

50 remaining 37 of the final element, which is to remain in sight, has a dimension equal to the dimension of the sectional element in order to perform the aesthetic function of a plug;

- according to a first peculiar feature, the final elements 9 and 14 are provided, at the terminal part of the adjustment part, with an inclined surface 35;

- the final elements 9 and 14 also have a possible locking pin 31;

55 - according to a second peculiar feature, the upper guide 10 is not fixed directly to the corresponding surface of the opening, but can be freely moved away from it, remaining, however, guided on an element in internal section 11, which in turn, it is fixed to said opening surface;

- according to a third peculiar feature, at the ends of the guide 10 two L-shaped fittings 8 are provided fitted in a notch deliberately designed 32 of the guide itself and fixed therein by

screw means 27; said accessories have an interlocking element 28 (which is already known in itself) but in addition to this they have an innovative elongated part that projects perpendicular to the guide 10 and which is provided with an inclined surface 29, a groove 38 and an element mechanical interlocking 33 which is designed to fit in the notch 34 of the element in section 15;

5 - in accordance with a fourth peculiar feature, the guide section element 10 has the possibility of sliding with respect to the fixed section element 11 only in an orthogonal direction to the latter, while any other movement is avoided thanks to an element 12, fixed to the opening by means of the screw 24, which is obliged to remain inside a slot 38 present in the accessory 8; said sliding is limited to the height of the element in section 11, by an appropriate choice of the point of attachment to the wall of the element 10 12, since the element in guide section 10 can move away from the wall of the opening only to the one point where the accessory 8 reaches the end of the groove 38, thus obtaining that the element in section 10 cannot be decoupled from it; Y

- the elements in section 15 and 17 are preferably provided with a hole 36 that will house the pin 31 of the respective end elements 9 and 14.

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[0043] The above elements allow rapid assembly, a cross-sectional dimension of the product that is

smaller than that of the known technique, and a system for compensating for possible differences between the size of the opening and that of the screen that does not change the degree of penetration of the sheet 2 into the guide 10.

[0044] In this regard, it should be noted that, in accordance with the invention, it is substantially foreseen

provide a kind of rigid perimeter frame, composed of the elements in fixed section 15, 17 and the elements in guide section 10, 18, within which the pleated screen 2 is stretched or compressed by manipulating the handle 16. The idea of The invention lies in having corner elements designed 8, 9, 14, 22, 25 to couple the four elements in section 15, 17, 10, 18 to obtain a precise and stable coupling of the elements themselves 25 in section, assigning the function of compensation of possible dimensional differences between the opening and the structure of the screen to an additional sectional element 11 cooperating with one of the four sectional elements of the frame, preferably the upper guide 10.

[0045] Advantageously, this makes it possible to obtain a fast and precise assembly, without any danger of the pleated screen coming out of the guides, in the case where the size of the opening is larger than that of the structure

installed in them.

[0046] The assembly of the elements in section 15 and 17, as described in Figures 7, 8 and 9 (which considers the side of the final element 9, but applied identically to the side of the final element 14), begins by

35 fit the element into a slightly inclined adjusted section. After the final element 9 has been engaged in the protuberance 28, the sectional element is rotated to reach an orthogonal configuration to the guide 10. The protuberance 28 and the surface 30 of the final element come into contact, and the element in section It is held against the opening surface. Simultaneously, the inclined surface 29 comes into contact with the corresponding inclined surface 35, determining the complete interlocking of the final element 9 with respect to the guide 40 10 through the L-shaped accessory 8. Without the possibility of error, the space between the element in section 10 and the element in section 15 is exactly equal to the height of the visible part 37 of the final elements, with the aesthetic result illustrated in Figure 6. Finally, the external lateral projection 33 of the groove 38 engages in the notch 34 of the element in section 15, and this makes the corner perfectly orthogonal.

[0047] To complete the assembly, it will be sufficient at this point to attach the lower end element 19 of

element in section 15 in the lower guide 18 (as conceived according to the known technique), and, as can be seen in Figure 9, when lowering the element in section 15, also the element in guide section 10 will fall accordingly, compensating any possible difference between the size of the opening and the size of the screen, without the need for any adjustment intervention by the installer. The distance (or space) that is created between the opening and the guide 10 is closed and compensated by the fixed section element 11.

[0048] Advantageously, as already indicated, the sheet 2 is always in the correct position, occupying

the guide 10 to the bottom of it with the best possible result in terms of light and insect tightness, unlike the known solution in which it is possible for the sheet to penetrate only slightly into the upper guide 55 in the case of dimensional errors, thus determining a net reduction of the hiding capacity of the sheet.

LEGEND

1) screen set;

2) pleated sheet;

5 3) fixed upright assembly with respect to the side of the sheet;

4) fixed sliding handle assembly with respect to one side of the blade (opposite to the fixed one with respect to the assembly 3)

5) upper guide assembly;

6) lower guide assembly;

7) locking post assembly;

10 8) accessory belonging to the assembly 5 that can be locked with respect to the element in section 10 and which is convenient to provide the corner joint between the assembly 5 and the assemblies 3 and 7;

9) end plug of the element in section 15 which agrees to provide the corner joint between the assembly 5 and the assembly 3;

10) element in guide section;

15 11) element in compensation section;

12) bush allowing the restriction of the accessory 8 allowing the possibility of sliding in the compensation direction;

13) end plug of the element in section 16;

14) end plug of the element in section 17 which agrees to provide the corner joint between the assembly 5 and the assembly 7;

15) element in fixed section with respect to one side of the sheet;

16) element in section (or sliding) of handle;

17) element in closing section;

18) element in guide section;

25 19) end plug of the element in section 15;

20) end plug of the element in section 16;

21) end plug of the element in section 17;

22) accessory to block sets 3 and 7 with respect to set 6;

23) locking accessory;

30 24) fixing screw;

25) fixing screw;

26) fixing screw;

27) clamping screw to fix the accessory 8 with respect to the element in section 10;

28) interlocking element present in 9 and 14;

35 29) inclined surface present in the end caps 9 and 14;

30) input portion for interlocking element 28;

31) locking pin present in the end caps 9 and 14 to engage the hole 36;

32) seat for accessory 8;

33) interlocking element for projections 34;

40 34) projections for coupling with the locking element 33 and the accessory 23;

35) inclined surface for engagement with surface 29;

36) hole to accommodate pin 31;

37) side wall facing the final elements 9 and 14;

38) sliding groove.

Four. Five

Claims (12)

1. A compensation system for screens for window or door openings, such as, for example, mosquito nets and blinds, comprising at least one pleated sheet (2) inserted in a structure 5 perimeter that can be fixed at least on two sides opposite the opening to be hidden, said system comprising elements for the connection of the corners of the perimeter structure of the screen, that is, for the connection of the ends of the elements in section of guide (10, 18) and of the vertical sectional elements (15, 17) of the structure, said system being characterized in that said connecting elements are designed to provide a rigid perimeter frame constituted by said fixed vertical sectional elements ( 15, 17) and 10 said elements in guide section (10, 18) within which the pleated screen (2) is stretched / compressed by moving at least one element in mobile section or "handle" (16); in addition, an additional section element (11) is provided, which is fixed to the opening in which the screen is installed and is designed to cooperate with at least one of the elements in guide section (10) - by means of a telescopic coupling in a direction substantially transverse to the guide section element itself - to compensate for the dimensional differences between said perimeter structure containing the sheet (2) and the opening in which it is installed; in which all elements in section of the structure have one and the same transverse dimension with respect to the plane of the own screen 2. The compensation system according to the preceding claim, characterized in that said perimeter structure or frame comprises two elements in vertical section (15 and 17) parallel to the fold, which they can be fixed to the opening where the screen is installed, of which at least one (15) is connected to one side of the pleated sheet (2), as well as two other elements in guide section (10 and 18) orthogonal to the first, which have a guiding function for the sheet itself; said mobile sectional element (16) being located within said perimeter structure, which is parallel to said vertical sectional elements (15 and 17) that are parallel to the fold and is free to slide with its ends in the sectional elements of guide (10 and 18); said element in mobile section (16) being connected to the pleated sheet (2) on the opposite side from that connected to the element in vertical section (15). 3. The compensation system according to the preceding claim, characterized in that, in the 30 upper and lower ends of each of the elements in vertical and mobile section (15, 16 and 17) parallel to the fold, there are accessories called "final elements" or "plugs" (9 and 19, 13 and 20, 14 and 21), whose The function is to close the ends of the elements in section and allow, together with the components (8 and 22) placed at the ends of the elements in the guide section (10 and 18), to fix the elements in section in the opening. 35 4. The compensation system according to the preceding claim, characterized in that: - the elements in guide section (10 and 18) and the elements in vertical and mobile section (15, 16 and 17) perpendicular to them have the same transverse dimension with respect to the screen plane to minimize the 40 transversal dimension of the structure and improve their aesthetics; - the final elements (9, 13 and 14) are shaped so that the part to be received in the guide section element (10) has a reduced transverse dimension that is very close to the transverse dimension of the pleated sheet (2): only the remaining part (37) of the final element, which must remain in sight, has the same size as the sectional element itself to perform the aesthetic function of the cap; Y 45 - the final elements (9 and 14) of the fixed sectional elements have, in the terminal part of the adjustment part, an inclined surface (35). 5. The compensation system according to the preceding claim, characterized in that the final elements (9 and 14) of the fixed vertical sectional elements have a locking pin (31). fifty The compensation system according to claim 4 or claim 5, characterized in that the element in upper guide section (10) is not fixed directly to the corresponding surface of the opening, but can move freely from the latter , however, being guided with sliding coupling in said additional section element (11) which is internal to said element in section of Guide (10) and is fixed to said opening surface. 7. The compensation system according to claim 3, characterized in that at the ends of the guide section element (10) are said accessories (8), which are L-shaped and are mounted on a notch provided deliberately (32 ) of the element itself in the guide section and fixed therein by means of a screw (27) or other suitable means; said accessories having an interlocking element (28), as well as an innovative elongated part that projects perpendicular to the guide section element (10) and which provides an inclined surface (29), a groove (38) and an interlocking element mechanical (33) to cooperate with a slot provided deliberately (34) of the fixed section element (15) which is connected to one side of the pleated sheet (2). 8. The compensation system according to the preceding claim, characterized in that the element in guide section (10) can slide with respect to the element in additional fixed section (11) only in an orthogonal direction to the latter, while avoiding any other movement thanks to an element (12), 10 fixed to the opening by means of a screw (24), which is limited to staying inside the groove (38) present in the accessory (8); said sliding of the element (12) in the groove (38) is not greater than the height of the element in additional section (11) so that the element in guide section (10) cannot be decoupled from the element itself in section (11) . The compensation system according to the preceding claim, characterized in that the Fixed vertical sectional elements (15 and 17) have a hole (36) that serves to house a pin (31) of the respective end elements (9 and 14). 10. The compensation system according to the preceding claim, characterized in that each one of the fixed sectional elements (15 and 17) can be installed initially being inserted in a manner slightly inclined after the end element (9) has been coupled to the protuberance (28), the sectional element can be rotated to achieve an orthogonal configuration to the guide sectional element (10), where the projection (28) and the surface (30) of the final element come into contact and the sectional element itself is held against the surface of the opening; simultaneously, said inclined surface (29) is in contact with a corresponding inclined surface (35) of the final element, determining the complete interlocking of the final element (9) with respect to the element in guide section (10) through the accessory in L shape (8). 11. The compensation system according to the preceding claim, characterized in that, without the possibility of error, the space between the guide section element (10) and the fixed vertical section element (15) is 30 exactly equal to the height of the visible part (37) of the final elements. 12. The compensation system according to the preceding claim, characterized in that an external lateral projection (33) of the groove (38) is provided, designed to engage in the notch (34) of the element in fixed vertical section (15) to make the last and the element in guide section (10) perfectly 35 orthogonal to each other. 13. The compensation system according to the preceding claim, characterized in that the lower end element (19) of the element in fixed vertical section (15) is designed to fit in the lower guide (18), causing a downward movement of the element in vertical section (15) so that also the 40 element in guide section (10) will fall accordingly with respect to the element in additional section (11), thus compensating for any possible difference between the size of the opening and the size of the screen without any adjustment intervention by the installer