DESCRIPTION

The present invention refers to a control device for the slats of a blind with adjustable slats.

This type of window and/or door blind is commonly used as an exterior sun screen/windbreaker shutter.

There exists a typology of control devices that use modules enclosing in a more or less miniaturised manner a lever or gear system that acts upon the pivot pin of the slat, providing it with the required rotary motion. A control device such as this proves to be rather imprecise and has given rise to some defects such as incomplete closure of the slats in the parts furthest away from the control handle, mainly due to slack formed in the connections between the various modules.

An improved solution existing on the market provides for a longitudinal support body shaped like a stiff rod that encloses all of the working parts necessary for rotation of the slats. This control device comprises two opposite rods for synchronising the oscillation of rockers pivoted to the longitudinal support body. Each rocker bears a rotating driving pin of a slat. With this solution, the slats can oscillate properly in a synchronised manner. The drawback of this solution consists in the fact that the length of the support body must be pre-establ ished in the construction phase, and thus also the number of slats to be assembled. In some cases, the support body can be cut so as to obtain smaller sizes, but the procedure is relatively complex and uneconomical, and it is not well received by the market. Manufacturers of controls, distribution warehouses and manufacturers of window and door frames pre fer to overcome this problem with a vast supply on hand. The measurements normally present on the market for the support body range from a length of about 35 cm to 220 cm. For a number of slats ranging between 6 and 36, a warehouse that aims to have an adequate assortment should therefore keep about 30 different sizes ready. Over the years, some firms have proposed an extremely long support body to be cut, as a solution to this issue, but this type of product has not met with success, owing to transportation and storage difficulties, as well as the above-mentioned difficulties in cutting them to the desired size. Moreover, given that for various reasons ranging from aesthetic to technical aspects, the typologies of the slats present on the market are varied, as are the shape and size of the small cap housing them, the assortment must be increased in terms of the various typologies of slats and the colours that one intends to have available.

There fore, the technical task of the present invention is to realise a control device for the slats of a blind with adjustable slats that makes it possible to overcome the above- described technical drawbacks of the prior art.

Within the scope of this technical task, an aim of the invention is to realise a control device for the slats of a blind with adjustable slats, which on the one hand proves to be extremely precise, simple and economical, and on the other hand, allows for simplification of the logistics of transport and storage of supplies.

The technical task, as well as the stated and other aims, according to the present invention, are achieved by realising a device for controlling the slats of a blind with adjustable slats that comprises a rotating longitudinal support body of rockers connected by rods opposite each other for the synchronisation of the oscillation thereof, characterised in that said opposite rods are flexible and in that the longitudinal support body is longitudinally divided into a plurality of modules along which the rods extend longitudinally.

Preferably, each module rotationally supports a corresponding rocker.

The basic principle underlying the control device is the segmentation of the longitudinal support body, which through a thorough study of the dynamics of the winding phase, is capable of ensuring control without interruptions for theoretically unlimited lengths.

The control device can be used as a strip, and given that only the synchronising rods exhibit longitudinal continuity, the control device can be brought to the desired length by cutting the rods with simple industrial scissors.

it is not hard to imagine that this represents a revolutionary step for the sector, as a single item replaces the entire stock in terms of sizes.

Preferably, the modules are serially connected by means of articulated connection means suitable for permitting winding of the support body as a consequence of an elastic flexion of the rods.

Preferably, the articulated connection means comprises at least one elastic tab that is lockable in a seat by means of a snap-fit coupling tooth.

Apart from the cutting of the rods, no further cuts are required to obtain the desired length of the control device, in that adjacent modules can be disconnected one from the other in an extremely simple manner.

Preferably, the rocker has a rotating driving pin of a bushing that is integral to a cap for a slat, the bushing being, in turn, engaged in a rotating seat passing through the thickness of a base wall of the module.

Preferably, the lateral coupling surfaces between the bushing of at least: one cap for a slat and the driving pin have conjugated formations for a friction rotating coupling between said bushing and said driving pin.

in particular, it is convenient to have a friction rotating coupling for all the caps, with the exception of the cap for the slat where the rotating means for driving the rockers operates, so as to enable effective transmission of the command.

Preferably, the rods are configured as laminae preferably having longitudinal tracts of structural sti ffening with a substantially non-flat cross section and longitudinal tracts with a substantially flat cross section so as to facilitate flexion.

Preferably, the rods configured as laminae have engagement holes for pins for coupling with said rockers, said holes being made without removal of material in such a manner as to define collars for reinforcement of the wall thickness of the rods. Pre ferably, the cylindrical bushing has external ribbing suitable for reducing the contact surface with the said rotation seat thereof.

Preferably, the driving pin has an axial cavity, in which a burglar-resistant system plug can be positioned.

Preferably, the module has one or more elastic elements of compensation for the differential thermal expansion to which it may be subjected with respect to the rods. Additional characteristics of the present invention are also defined in the claims that follow.

Further characteristics and advantages of the invention will become more apparent from the description of a preferred, but not exclusive, embodiment of the control device for the slats of a blind with adjustable slats according to the invention, said embodiment being illustrated by way of illustrative and non-limiting example in the accompanying drawings, wherein: - Figure 1 is a cutaway view of a blind mounted with the device for controlling the slats according to the invention;

- Figure 2 shows a section of the control device in the wound configuration of the longitudinal support body;

- Figure 3 shows the rocker applied to the bushing of the cap for a slat;

- Figure 4 shows the cap for a slat;

- Figure 5 shows the rotating driving rocker of the cap for a slat;

- Figure 6 is a plan view of a cap for a slat, highlighting in section the coupling of the bushing thereof with the driving pin;

- Figure 7 is a plan view of the module to which the cap for a slat is applied;

- Figure 8 is a longitudinal section of an assembly comprising two adjacent connected modules of the control device;

- Figure 9 shows the configuration assumablc by the assembly appearing in Figure 8 as a consequence of the differential thermal expansion to which the modules are subjected with respect to the rods.

With reference to the figures cited, a device for controlling 1 the slats 2 of a blind 3 with adjustable slats 2 is shown.

The control device 1 is applied in a known manner inside an upright of the frame of the blind 3 and it extends longitudinally in such a manner as to face one end of all the slats 2 that must be driven.

The control device 1 comprises a rotating longitudinal support body 7 of rockers 6 connected by rods 4, 5 opposite each other for the synchronisation of the oscillation thereof.

There is also provided a specific means of a known type, which is not illustrated, for the manual or motorised rotating driving of the rockers.

Advantageously, the rods 4, 5 opposite each other are flexible and the longitudinal support body 7 is longitudinally divided into a plurality of modules 8 along which the two rods 4, 5 extend longitudinally.

Each rocker 6 is rotationally supported by a corresponding module 8 and has a rotating driving pin 9 of a bushing 10 that is solidly constrained to a cap 1 1 for a slat 2.

The rocker 6 and the pin 9 are made in a single piece, as are the bushing 10 and the cap 1 1.

In particular, the bushing 10 is fitted on the driving pin 9 and has an internal, lateral surface 14 press-fitted with the external, lateral surface 1 5 of the driving pin 9.

The coupling surfaces 14 and 1 5 have respective conjugated formations 16, 17, for example a series of rounded recesses and corresponding rounded projections, which ensure a friction rotating coupling between the bushing 10 and the driving pin 9.

In this manner, when the bushing 10 is subjected to greater stress than necessary during normal operation of the control device 1 , for example when the user activates the slat 2 directly by hand, it can actuate a friction coupling with the driving pin 9, thereby obtaining a breakage prevention effect with respect to the control device 1. In order to prevent removal of a single slat 2 from the frame of the blind 3, the driving pin 9 has an axial cavity 25 in which a burglar-resistant system plug 52 can be positioned that passes axially through the bushing 10.

The cap 1 1 is pivoted to the module 8 by means of the bushing 10 of the cap 1 1.

In particular, the bushing 10 is coaxially engaged in a cylindrical, rotating seat 12 passing through the thickness of a flat, base wall 1 3 of the module 8. More specifically, the bushing 10 is inserted into the seat 12 thereof from one side of the base wall 13 of the module 8, whereas the driving pin 9 is inserted into the bushing 10 from the opposite side of the base wall 13 of the module 8.

With respect to the base wall 13 of the module 8, the cap 1 1 is therefore positioned on the side opposite the rocker 6, whereas the synchronising rods 4, 5. again with respect to the base wall 13, are positioned on the same side as the rocker 6, specifically between the rocker 6 and the base wall 1 3 of the module 8.

The bushing 10 has special ribbing 19 on the external lateral surface 1 8 suitable for reducing the contact surface with the rotation seat 12 thereof.

In this manner, it is possible to avoid jamming caused by the accumulation of dirt, and also, at the same time, decrease the contact surface between the bushing 10 and the rotation seat 1 2 so as to increase the smoothness of the rotation of the bushing 10. The rocker 6, which has an axis of oscillation coincident with the axis of the rocker 10 and of the driving pin 9, is provided with two arms 21 , 22 of equal length and diametrically aligned on the side opposite the axis of oscillation 20.

Each rocker 6 is hinged to the rods 4, 5. by means of the fitting of pins 23. 24 present at the ends of the arms 21 , 22 thereof, in respective through holes (unillustrated) provided in the rods 4, 5.

The configuration of the rods 4, 5 must ensure, with the least possible thickness, very high flexibility during winding and at the same time, adequate stiffness in the longitudinal direction.

The rods 4, 5 are thus configured as laminae having tracts 40 of structural stiffening and tracts 41 suitable for facilitating flexion.

In particular, the tracts 40 have a substantially non-flat cross section, for example V- shaped, as shown.

However, the tracts 41 which are at least the tracts that have holes where the hinging pins 23, 24 are applied, have a substantially flat cross section.

The lamina conveniently also has connection tracts 43 between the tracts 40 and the tracts 41 .

With respect to the tracts 40, the lie of the tracts 41 is chosen in such a manner as to form depressions along the laminae in points where the holes for the hinging pins 23, 24 are positioned.

These holes in the rods 4, 5 for hinging the rockers are made possibly without removal of material in such a manner as to define collars for reinforcement of the wall thickness of the laminae so as to increase the engagement surface for the pins 23, 24.

Advantageously, the modules 8 are serially connected by means of articulated connection means suitable for permitting winding of the longitudinal support body 7 as a consequence of an elastic flexion of the two rods 4, 5.

The articulated connection means comprises at least one elastic tab 30 that is lockable in a seat 26 by means of a snap-fit coupling tooth 27.

More specifically, in order to lock the elastic tab 30 in the seat 26, the elastic tab 30 is provided with a fashioned closed slot 50 passing through the thickness thereof and engageable by the coupling tooth 27.

Advantageously, each module 8 comprises a coupling tooth 27 and an elastic tab 30 at each end thereof, to be connected to the adjacent modules 8.

At these ends of the module 8. the base wall 13 has a projection 33 on which the coupling tooth 27 is positioned. The projection 33 laterally delimits a compartment 34 of a complementary shape on which the tab 30 projects.

The coupling tooth 27 and the tab 30 are positioned on the side of the base wall 1 3 facing the rocker 6.

On the same side, perimetrically to the projection 33, the base wall 13 has an orthogonal wall 29 that has a window 28 defining the seat 26.

In the configuration of the connection of two adjacent modules 8, the projection 33 at the end of the base wall 1 3 of a first module 8 occupies the compartment 34 delimited by the projection 33 at the end of the base wall 1 3 of the second module 8, and each tab 30 is inserted in the respective seat 26, where it is retained owing to the engagement of the coupling tooth 27 in the slot 50.

The articulation of the connection between the modules 8 is thus obtained owing to the elastic flexibility of the tab 30, which allows for modification of the relative orientation between the modules 8.

To disconnect the modules 8 after cutting the rods in order to give the control device 1 the right size, it is sufficient to lift the tab 30 as needed to disengage it from the coupling tooth 27 before taking it out of the seat 26.

To connect the modules 8 during assembly of the control device 1 , the tab 30 is instead inserted into the seat 26 until the apical part of the tab 30 meets an inclined surface 5 1 of the tooth 27, which lifts the apical part of the tab 30 as needed to have it pass over the same tooth 27 in such a manner that the latter can slip into the slot 50 located on the tab 30 in a position further to the rear.

Therefore, a windable control device can be composed with any number of modules 8, from which to detach the tract of a length suited to the specific application. The connection thus structured between the modules 8 affords optimal resistance of the support body 7 to torsion, while allowing for longitudinal flexion of the support body 7.

Advantageously, the module 8 also has one or more elastic elements of compensation for the di fferential thermal expansion to which it may be subjected with respect to the rods 4, 5.

In this manner, in the case in which the constituent material of the module 8 differs from that of the rods 4, 5, it is possible to maintain a substantially constant interaxis between the modules 8 and thus between the slats 2, and enable movement free of dimensional tension.

The elastic element of compensation comprises a buffer 3 1 supported by the base wall 1 3 on the same side as the wall 29.

The buffer 3 1 extends from the attachment zone of the tab 30 to the base wall 13, and has a surface 32 facing the tab 30 and inclined in such a manner as to project over the compartment 34 so as to interfere with the wall 29 present on the projection 33 that occupies the compartment 34.

Figures 8 and 9 show the compensation carried out by the buffer 3 1 for differential thermal expansion, as the buffer 3 1 , by varying the thrust performed according to variations in thermal expansion, makes it possible to maintain a uniform pitch between the modules 8 under all types of climatic conditions.

Lastly, peri metrically and on the same side in which the wall 29 and the buffer 3 1 are provided, the base wall 13 of the module 8 provides specific members 45 for fastening the frame of the blind 3 to the upright.

The device for controlling the slats of a blind thus conceived is susceptible to numerous modifications and variants, all of which falling within the scope of the inventive concept; moreover, all the details may be replaced with technically equivalent elements.

The materials used, as well as the dimensions, may in practice be of any type according to requirements and the state of the art.