GB2292409A - Motorised retractable louvre assembly - Google Patents

Abstract

Each end of a plurality of rotatable louvres (2) is mounted for movement along a guideway (9) closed at one end (9a). The guide assembly comprises a mounting plate (7) in which a plurality of aligned members (8) are rotatably mounted with the guideway (9) formed by aligned channels (9) extending across the faces of the members (8). Rotatable members (8) are provided to non-rotatably engage the ends of each louvre (2) whilst being rotatably mounted on mounting plates (7). The louvres (2) are connected to adjacent louvres by links (3). The endmost louvre (2a) is movable along said guideway (9) by motor driven means. When the endmost louvre (2a) docks in the closed end (9a) of the guideway (9), continued movement of the moving means (11) moves the whole guide assembly (7, 8) and causes louvre tilting means (5, 6) to engage with fixed drive means (4) to rotate the members (8) and the louvres (2) connected thereto in synchronism. <IMAGE>

Description

A MOTORISED RETRACTABLE LOUVRE STRUCTURE DESCRIPTION The present invention relates to a motorised retractable louvre structure which has particular, but not exclusive, application to blinds which can be of the standard venetian type or of the larger aerofoil or fin type.

Motorised retractable blind structures are well known and include a plurality of parallel louvres which are coupled to cables so that the blinds may be extended and retracted.

Means are also included to vary the angle of the louvres.

Motorised blinds of this type are known wherein one motor is used both to raise the blinds and to control the degree of tilt of the louvres. The motor drives ladders and tapes to raise and lower the louvres and a friction drive is used to vary the angle of the louvres. However, a problem with blinds of this type is that the tilt of the louvres cannot be finely adjusted and the closure of the louvres may not be consistent particularly with blinds covering larger drops or areas.

According to a first aspect of the present invention, there is provided a motorised retractable louvre structure comprising a louvre assembly having a plurality of louvres, control means coupled to the louvre assembly to drive it from a retracted configuration to an extended configuration, and a rotary member provided with docking means drivingly engaged by complementary means provided on one of the louvres when the louvre assembly is in said extended configuration, the rotary member being translatable by said one of the louvres assembly on further operation of the control means, wherein the rotary member is provided with a mechanism whereby it is caused to rotate during translation thereby rotatably driving said one of the louvres about its longitudinal axis.

It can be seen that a structure according to the present invention requires only a single control. Initially the control, for instance a steel cable, stainless steel tape or light chain, drives the louvre assembly into an extended configuration. Further operation of the control then causes the angle of the louvres to change. Thus, a single motor, for example an electric motor, may be used to operate the structure without the need for complicated gearing systems.

Only one louvre need be driven directly by a rotary member, the other louvres may be coupled to that louvre so as to move in unison. However, preferably, further rotary members are provided for drivingly engaging respective louvres, each further rotary member being caused to rotate by said mechanism on further operation of the control means thereby rotatably driving its respective louvre about the longitudinal axis thereof. This preferred arrangement allows the angle of the louvres to be finely adjusted and consistent closure of the louvres to be ensured. This is particularly advantageous in the case of long blinds.

A problem suffered by conventional blind structures is that they are unsuitable for mounting at shallow angles or horizontally, for instance across the roof of a conservatory. The present invention in a preferred embodiment also addresses this problem. This preferred embodiment includes a guide for guiding the louvre assembly during extension, the guide comprising structures on the rotary members, wherein the docking means comprises a termination of the guide and the guide structures drivingly engage the louvres for rotation thereof. Conveniently, the guide structures define a channel for guiding the louvre assembly during extension. However, the guide structures may define a rail to be received in slots provided at one end of each of the louvres.

Preferably, the mechanism comprises a pinion wheel on the or each rotary member and a rack engaged by the or each pinion wheel. These may be toothed. However, a friction coupling may be found appropriate under certain circumstances.

Preferably, the louvres are coupled by links and the louvre assembly is concertinaed in the retracted configuration.

These links may be articulated and the louvres stacked one upon another when the louvre assembly is in its retracted configuration.

Preferably, the louvres are driven from both ends for varying their angle.

According to a second aspect of the present invention,there is provided a motorised retractable louvre structure comprising a plurality of louvres mounted at each end for movement along a guideway closed at one end provided in a guide assembly, tilting means operable to tilt the louvres, means connecting the louvres to each other and the endmost louvre having moving means connected thereto operable by a motor to move the louvres along said guideway, the arrangement being such that when the endmost louvre docks in the closed end of the guideway, continued movement of the moving means in the same direction moves each guide assembly and the louvre tilting means engages with fixed drive means whereby the relative movement between the each moveable guide assembly and its associated fixed drive means results in the louvres rotating in synchronism.

Conveniently, the louvre tilting means associated with each guideway comprises a rotatable member, all of said rotatable members drivingly receiving one end of a louvre, each rotatable member having a channel extending across it except the endmost rotatable member whose channel is closed at one end, the channels in the rotatable members being alignable with each other to provide said guideway in the guide assembly.

Preferably, each rotatable member is a wheel and the channel extends diametrically across the width of each wheel except for the endmost rotatable member in which the channel is closed at one end.

In a preferred embodiment, each rotatable member has a pinion attached thereto engagable with the fixed drive means to tilt the louvres. Suitably, the fixed drive means is a toothed rack.

Conveniently, the louvre connecting means are pivotally attached to each louvre so that the louvres can stack in concertina fashion in their retracted position.

An embodiment of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 shows a blind incorporating a louvre structure according to the present invention in its retracted configuration; Figure 2 shows the blind of Figure 1 in its extended configuration; Figure 3 is an exploded view of the portion indicated by A in Figure 2; Figure 4a illustrates in section the portion indicated by A in Figure 2 with the louvres at a first angle; Figure 4b illustrates in section the portion indicated by A in Figure 2 with the louvres at a second angle; and Figure 5 shows the louvres of another embodiment in their retracted configuration.

Referring to Figures 1, 2 and 3, a blind is arranged to cover a window 1. The blind comprises a plurality of louvres 2, coupled by inextensible links 3. The links 3 each comprise a bar extending between two rings. A lug 12 extends longitudinally from each end of each louvre 2 and for most of the louvres 2 passes through rings of two adjacent links 3. The lugs 12 of the uppermost and lowermost louvres 2, however, pass through only a single ring.

A fixed rack gear 4 is arranged vertically on either side of the window 1. Two set ofs pinion gears 5 engage respective ones of the rack gears 4. The pinion gears 5 do not engage with each other. Each set of pinion gears 5 includes one pinion gear 5 for each louvre 2. Stub axles 6 of the pinion gears 5 of each set are received in holes provided in respective coupling bars 7, each of which couples all the pinion gears 5 in one set. A disc member 8 is attached coaxially to each of the pinion gears 5 opposite its stub axle 6.

Each of the disc members 8 has a channel 9 formed in its face opposite its pinion gear 5. The channels 9 extend diametrically across the disc member 8 with the exception of the channels 9 in the uppermost disc members 8 which extend only halfway across. The channels 9 in the disc members 8 within each set of pinion gears 5 can be aligned to form a single continuous guide channnel.

A recess 10 is located at the foot of the window 1 which contains the louvres 2 when the blind is retracted. Cables 11 coupled to a motor (not shown) are attached at each end of the uppermost louvre 2a to enable the blind to be extended from its retracted configuration.

The ends of the lugs 12 are shaped to be slidingly accepted by the channels 9. However, their shape is such that they cannot rotate within the channels 9.

The process of extending the blind will now be described.

Referring to Figure 1, the louvres 2 are initially concertinaed within the recess 2. To extend the blind, the cables 11 are pulled upwards by the motor (not shown). This pulls on the uppermost louvre 2 and causes it to rise, progressively bringing with it the other louvres 2. As the louvres 2 rise, their lugs 12 slidingly engage the lower end of the guide channel formed by the aligned channels 9 in the disc members 8 and are guided thereby during extension of the blind. The blind is fully extended when it reaches the position shown in Figure 3 where the lugs 12a of the uppermost louvres 2a dock in and abut the closed ends of the channels 9a in the uppermost disc members 8a.

The blind is retracted by reversing the direction of the motor (not shown) thereby reducing the pulling force on the cables 11 and allowing the louvres 2 to collapse and concertina into the recess 2.

The operation of adjusting the angle of the louvres 2 will now be described.

Referring to Figure 4a, when the extension of the blind is complete, the lugs 12a of the uppermost louvres 2a dock in and abut the closed ends of the channels 9a in the uppermost disc members 8a. The lugs 12 of the other louvres 2 are located centrally in the channels 9 in their respective disc members 8. This is ensured by the spacing function of the links 3.

Referring to Figure 4b, if the cables 11 continue to be pulled by the motor (not shown), the force is transfered to the uppermost disc members 8a via the lugs 12a on the upper louvre 2a. Since the upper pinion gears 5 are engaged with the rack gears 4, the uppermost disc members 8a can only rise under the influence of the applied force by rotating.

The other pinion gears 5 are constrained to move also by the coupling bars 7 and likewise must rotate.

Since none of the lugs 12 can rotate relative to the channels 9, the rotation of the pinion gears 5 causes the angle of all the louvres 2 to change as illustrated in Figure 4b. One quarter rotation of the pinion gears 5 is sufficient to move the louvres 2 from a horizontal position to a vertical position.

On reversing the motor (not shown), the force on the cables 11 is reduced and, the louvres 2 fall under the influence of gravity and their change in angle will be reversed. It can clearly be seen that the angle of the louvres 2 can be controlled to be anywhere between horizontal and vertical by pulling appropriately on the cables 11.

Referring to Figure 5, in another embodiment the louvres 2 are linked by articulated links 13. The articulated links 13 allow the blind to collapse so that the louvres 2 are stacked one above another rather than in the zig-zag manner which the one piece links shown in Figure 3 produces. The articulated links 13 have the advantage that the recess 10 may be considerable narrower and therefore less obtrusive.

The present invention can be applied to louvred structures other than Venetian blinds. For instance, the arrangement described above can be adapted for larger louvres, including aerofoil "fin' systems. In the case of large louvres, the the discs need not be increased in diameter to correspond to the spacing of the louvres. Instead, fixed guide sections could be located between adjacent discs so that a continuous guide is provided for the louvres during extension and retraction.

The present invention has be explained with reference to a vertically mounted blind which is raised to its extended configuration. However, the present invention is applicable to louvre structures which extend downwardly or horizontally. Furthermore, the guides maintain the louvres in the correct relative positions and enable a structure according to the present invention to be applied where the plane of the blind or other structure must be inclined or horizontal.

In the described embodiments, the louvres are capable of being tilted through 900. However, the arrangement of the present invention may be used to rotate louvres through any angle. However, if the louvres are to rotate by more than 900, the cord of the louvres must be no more then the spacing between adjacent louvres.

If gravity is not available for extending or retracting the structure, the control cables can be formed into loops with both ends joined to the leading louvre. The cable loops may be manually operated or driven by a motor.

Claims (17)

1. A motorised retractable louvre structure comprising a louvre assembly having a plurality of louvres, control means coupled to the louvre assembly to drive it from a retracted configuration to an extended configuration, and a rotary member provided with docking means drivingly engaged by complementary means provided on one of the louvres when the louvre assembly is in said extended configuration, the rotary member being translatable by said one of the louvres on further operation of the control means, wherein the rotary member is provided with a mechanism whereby it is caused to rotate during translation thereby rotatably driving said one of the louvres about its longitudinal axis.

2. A louvre structure according to claim 1, wherein further rotary members are provided for drivingly engaging respective louvres, each further rotary member being caused to rotate by said mechanism on further operation of the control means thereby rotatably driving its respective louvre about the longitudinal axis thereof.

3. A louvre structure according to claim 2, comprising a guide for guiding the louvre assembly during extension, the guide comprising structures on the rotary members, wherein the docking means comprises a termination of the guide and the guide structures drivingly engage the louvres for rotation thereof.

4. A louvre structure acording to claim 3, wherein the guide structures define a channel for guiding the louvre assembly during extension.

5. A louvre structure according to any preceding claim, wherein the mechanism comprises a pinion wheel on the or each rotary member and a rack engaged by the or each pinion wheel.

6. A louvre structure according to claim 5, wherein the or each pinion wheel and the rack are toothed.

7. A louvre structure according to any preceding claim, wherein the louvres are coupled by links and the louvre assembly is concertinaed in the retracted configuration.

8. A louvre structure according to claim 7, wherein the links are articulated and the louvres are stacked one upon another when the louvre assembly is in its retracted configuration.

9. A louvre structure according to any preceding claim wherein a rotary member is provided at both ends of said one of the plurality of louvres.

10. A motorised retractable louvre structure comprising a plurality of louvres mounted at each end for movement along a guideway closed at one end provided in a guide assembly, tilting means operable to tilt the louvres, means connecting the louvres to each other and the endmost louvre having moving means connected thereto operable by a motor to move the louvres along said guideway, the arrangement being such that when the endmost louvre docks in the closed end of the guideway, continued movement of the moving means in the same direction moves each guide assembly and the louvre tilting means engages with fixed drive means whereby the relative movement between the each moveable guide assembly and its associated fixed drive means results in the louvres rotating in synchronism.

11. A retractable louvre assembly as claimed in claim 10 wherein the louvre tilting means associated with each guideway comprises a rotatable member, all of said rotatable members drivingly receiving one end of a louvre, each rotatable member having a channel extending across it except the endmost rotatable member whose channel is closed at one end, the channels in the rotatable members being alignable with each other to provide said guideway in the guide assembly.

12. A retractable louvre assembly as claimed in claim 11 wherein each rotatable member is a wheel and the channel extends diametrically across the width of each wheel except for the endmost rotatable member in which the channel is closed at one end.

13. A retractable louvre assembly as claimed in claim 12 wherein each rotatable member has a pinion attached thereto engagable with the fixed drive means to tilt the louvres.

14. A retractable louvre assembly as claimed in any of claims 10-13 wherein the fixed drive means is a toothed rack.

15. A retractable louvre assembly as claimed in any of claims 10-14 wherein the louvre connecting means are pivotally attached to each louvre so that the louvres can stack in concertina fashion in their retracted position.

16. A retractable louvre structure substantially as hereinbefore described with reference to Figures 1 to 4b of the accompanying drawings.

17. A retractable louvre structure substantially as hereinbefore described with reference to Figure 5 of the accompanying drawings.