WO2012095424A1

WO2012095424A1 - Covering for an architectural opening

Info

Publication number: WO2012095424A1
Application number: PCT/EP2012/050312
Authority: WO
Inventors: Robert Jan Ponsen
Original assignee: Hunter Douglas Industries B.V.
Priority date: 2011-01-13
Filing date: 2012-01-10
Publication date: 2012-07-19
Also published as: AU2012206606A1; EP2663725A1; PL2663725T3; NO2663725T3; AU2012206606B2; EP2663725B1

Abstract

A covering (10) for an architectural opening and a method of controlling tilting of suspended blind slats (14) of a covering (10) including a head rail (12) with a tilt controller (20) for controlling a tilt of blind slats (14) suspended from the head rail (12). The tilt controller (20) includes a tape spool (22) having an outer circumference with a tapered grove (30) extending therearound and extending radially inwardly, a support wedge (40) having opposite ends (42, 44) and, between the opposite ends, having an arcuate extent fitting within and for frictional engagement with the tapered groove (30) and a flexible support (16) having a connection to the support wedge (40) and extending either diametric side of the tape spool (22) to support opposite respective edges of the blind slats (14). The flexible support (16) extends from the connection and between the support wedge (40) and the tape spool (22).

Description

COVERING FOR AN ARCHITECTURAL OPENING

The present invention relates to a covering for an architectural opening and, in particular, a tilt controller and a method for controlling the tilt of suspended blind slats.

It is known from documents such as DE 36 25 365 A and DE 199 21 465 C to control the tilt of horizontal blind slats suspended beneath a head rail by rotation of the same shaft used to raise or lower the blind slats. The head rail includes a rotatable shaft, which is selectively rotatable so as to wind or unwind at least one lift cord for raising and lowering the blind slats with respect to the head rail. The shaft also rotates at least one tape spool used for tilting the blind slats. A ring segment has a frictional engagement with an outer periphery of the tape spool and, hence, is rotated with the tape spool. Carrying members, which are connected with opposite respective edges of the blind slats, are connected to the ring segment. In this way, when the tape spool is rotated with the shaft, the ring segment also rotates so as to tilt the blind slats.

Stops are provided adjacent the outer circumference of the tape spool and respectively limit rotation of the ring segment in either direction. In this way, when the ring segment abuts one of the stops, further rotation of that ring segment is prevented, such that further tilting of the blind slats is halted. However, by overcoming the force of the frictional engagement between the ring segment and the tape spool, the tape spool and the winding shaft that drives it can continue to rotate such that winding or unwinding of the lift cords for the blind slats allows raising or lowering of the blind slats.

The present application recognises a problem with this earlier arrangement, namely that when the blind slats are tilted in one direction, for instance with clockwise rotation of the tape spool such that rearward edges of the blind slats are raised above the forward edges, then the weight of the blind slats is reduced on the forward/clockwise portion of the ring segment such that the overall frictional engagement force between the ring segment and the tape spool is reduced. As a result, the ring segment according to the prior art tends to slip with respect to the tape spool prior to engaging the respective stops such that it is no longer possible to tilt the blind slats to the fully tilted orientation as intended.

According to the present invention, there is provided a method of controlling tilting of suspended blind slats of a covering using a flexible support supporting opposite respective edges of the blind slats, the method including:

extending the flexible support either diametric side of a rotatable tape spool having an outer circumference with a tapered groove extending therearound and extending radially inwardly;

connecting the flexible support to a support wedge having opposite ends and, between the opposite ends, an arcuate extent fitting within and for frictional engagement with the tapered groove; and

extending the flexible support from the connection to the support wedge between the support wedge and the tape spool.

According to the present invention, there is provided a covering for an

architectural opening including a head rail with a tilt controller for controlling a tilt of blind slats suspended from the head rail, the tilt controller including:

a rotatable tape spool having an outer circumference with a tapered groove extending therearound and extending radially inwardly;

a support wedge having opposite ends and, between the opposite ends, having an arcuate extent fitting within and for frictional engagement with the tapered groove;

a flexible support having a connection to the support wedge and extending either diametric side of the tape spool to support opposite respective edges of the blind slats; wherein

the flexible support extends from the connection and between the support wedge and the tape spool. By extending the flexible support between the support wedge and the tape spool so that it runs underneath the support wedge, any force transmitted along the flexible support resulting from the weight of the blind slats is directed to the connection, rather than either of the opposite ends of the support wedge. As a result, compared with an arrangement in which the flexible support extends around the outside of the support wedge, a higher component of force is provided between, and normal to, the frictionally engaging surfaces between the support wedge and the tape spool. Hence, when the blind slats are fully tilted, a significant frictional engagement force still exists between the support wedge and the tape spool.

The respective edges of the blind slats on one or both sides may be joined and covered by a membrane so as to form a cellular shade.

The connection is provided at a central portion of the support wedge. The support wedge may include an inner side facing the tape spool and an outer side opposite the inner side. Although it would be possible to provide the connection on the inner side of the support wedge, by providing the connection on the outer side of the support wedge, it becomes possible to provide appropriate arrangements for the connection without concern of that connection interfering with relative movement between the support wedge and the tape spool.

The support wedge may define, on either side of the connection, throughholes between the outer side and the inner side. In this way, the flexible support may extend from the connection in opposite directions through the respective throughholes. Thus, although the flexible support connects with the support wedge on the outer side, it still extends between the support wedge and the tape spool.

The flexible support could be provided as a continuous member connected, at the connection, to the support wedge. The flexible support might instead include a first end and a second end both connected to the support wedge at the connection. The flexible support could be a single continuous member extending from the first end to the second end or could be provided as two or more members.

The flexible support can extend from the first end around one diametric side of the tape spool and extend from the second end around the other diametric side of the tape spool. In this way, the flexible support extends either diametric side of the tape spool to support the opposite respective edges of the blind slats.

The connection for connecting the flexible support to the support wedge may be embodied in any appropriate and convenient manner. However, where the flexible support includes a first end and a second end, the first end and the second end may include respective beads for connection with the support wedge. The connection may include a mounting portion for receiving and securing the respective beads so as to connect the first end and the second end to the support wedge. The mounting portion can include a slot or indentation having a size for receiving a respective bead or both beads.

The arcuate extent of the support wedge will influence the force of frictional engagement between the support wedge and the tape spool. The arcuate extent in some embodiments may be provided between 30 degrees and 200 degrees. In preferred embodiments, the arcuate extent may be provided between 140 degrees and 180 degrees.

Preferred embodiments of the support wedge include a pair of oppositely facing side walls for fitment within the tapered groove. Each of the side walls can be provided with respective frictional surfaces for frictional engagement with the tapered groove.

Although a single continuous frictional surface may be provided along each side wall, it is also possible to provide a plurality of discrete frictional surfaces for each side wall. In this respect, each side wall may include a respective frictional surface proximate each opposite end of the support wedge. This is advantageous in selectively reducing the force of frictional engagement between the support wedge and the tape spool by lifting one of the opposite ends of the support wedge out of, or at least away from, engagement with the tapered groove.

A plurality of tilt stops of different respective sizes may be provided for use with the tilt controller.

A tilt stop can be mounted adjacent the outer circumference of the tape spool, the tilt stop having end stops at opposite respective ends of the tilt stop spaced along the circumference of the tape spool for engagement with corresponding opposite ends of the support wedge. Each end stop is configured to lift the corresponding opposite end of the support wedge from the tapered groove so as to release frictional engagement between the support wedge and the tape spool.

As explained above, by providing the flexible support between the support wedge and the tape spool, it becomes possible to increase the force of frictional engagement between the support wedge and the tape spool for greater degrees of rotation of the support wedge with the tape spool. Rather than then merely relying upon the tilt stop forcibly preventing further rotation of the support wedge such that the tape spool must be rotated with sufficient force to overcome that frictional engagement, by providing end stops in the tilt stop that are configured to lift the corresponding ends of the support wedge from the tapered groove, the force of frictional engagement between the support wedge and the tape support can be reduced at exactly the position intended for maximum tilt of the blind slats.

The space between the end stops thus defines an extent of angular movement by which the tape spool can move the support wedge.

The tilt stop is preferably provided as an interchangeable part, thereby allowing the use of different tilt stops for different closure angles of slats and/or for different slat widths. Hence, the covering may be provided with at least one other tilt stop of a different size, thereby allowing adaptation of the covering for different closure angles and/or different slat widths.

As noted above, the head rail may include a rotatable winding shaft for selectively winding and unwinding at least one lift cord for raising and lowering the blind slats. The tape spool is preferably rotated with the winding shaft, either directly or by means of some connection.

In some embodiments, it may be preferable to provide a plurality of the tilt controllers as defined above spaced along the head rail, for example one proximate each end of the head rail.

The covering may be provided merely for use with a plurality of blind slats or may be provided together with a plurality of blind slats.

The invention will be more clearly understood from the following description, given by way of example only, with reference to the accompanying drawings, in which:

Figure 1 illustrates schematically a covering embodying the present invention; Figure 2 illustrates schematically an arrangement for lifting and tilting blind slats;

Figure 3 illustrates an embodiment of a tilt controller;

Figure 4 illustrates component parts of the tilt controller of Figure 3;

Figure 5 illustrates a cross-section through the tilt controller of Figure 3;

Figures 6(a) and (b) illustrate schematically a sub-optimal arrangement and an arrangement embodying the present invention; and

Figure 7 illustrates a support wedge and a tilt stop for use in the tilt controller of Figure 3.

The present invention relates to a tilt controller for a covering for an architectural opening. An example of such a covering is illustrated in Figure 1.

The covering 10 includes a head rail 12 beneath which are suspended a plurality of blind slats 14. As illustrated, the blind slats 14 are arranged in a vertical array with one slat above the other and with each of the blind slats arranged generally horizontally.

Although other orientations are also possible, the present invention is particularly advantageous when supporting the blind slats 14 under their own weight.

As illustrated, a flexible support 16 extends down along the opposite respective edges of the blind slats 14. In particular, the flexible support 16 is attached to the blind slats 14 so as to support them. This attachment may be achieved in any known or convenient manner, for instance securing the flexible support 16 directly to respective edges of the blind slats 14 or providing cross-members at least beneath each blind slat 14 so that the flexible support has the form of a ladder and the blind slats 14 rest on the cross- members.

In the illustrated embodiment, a flexible support 16 is provided towards each respective end of the head rail 12 so as to support the blind slats 14 towards their respective ends. Other arrangements are also possible and additional flexible supports 16 may be provided.

The flexible support 16 may be provided in any known or convenient manner, for instance as a cord, tape or chain.

Lift cords 18 are also provided extending down from the head rail 12. The lift cords 18 may be withdrawn into the head rail 12, for instance by winding, in order to lift the blind slats 14 up to the head rail 12 and, hence, expose the architectural opening otherwise covered by the covering 10. The lift cords 18 may operate in any known or convenient manner, for instance being attached to a lowermost one of the blind slats 14 or a bottom rail (not illustrated) positioned beneath the lowermost blind slat 14. The lift cords 18 may pass through respective apertures provided in the blind slats 14 or may pass along edges of the blind slats 14.

Figure 2 illustrates schematically the arrangement within the head rail 12 for lifting and tilting the blind slats 14. As will be discussed in greater detail below, the flexible support 16 extends from a tilt controller 20 including a rotatable tape spool 22. The tape spool 22 is rotatable by means of a rotatable winding shaft 24, which is also effective in winding and unwinding a lift cord 18. Thus, when the winding shaft 24 is rotated to wind or unwind the lift cord 18, it is along operable to rotate the tape spool 22 for transporting the flexible support 16 (up on one side and down on the other) to tilt the blind slats 14. As will be discussed in greater detail below, the tilt controller 20 includes a clutch mechanism allowing the tape spool 22 to continue to rotate once the blind slats 14 have reached full tilt.

Figure 3 illustrates a tilt controller embodying the present invention, and Figure 4 provides an exploded value of the components of the tilt controller of Figure 3.

As illustrated, the tilt controller 20 includes a housing formed from a lower portion 26 and an upper portion 28, which are secured together to define an internal cavity within which the tape spool 22 is housed.

The tape spool 22 has an axis of rotation about which it is rotatable and has an outer circumference within which is formed a tapered groove 30. As illustrated, the tapered groove extends around the entire circumference of this tape spool 22 and extends radially inwardly towards the axis of rotation.

Figure 5 illustrates a cross-section through the assembly of Figure 3 and shows a cross-section of the tapered groove 30 having a width, in an axial direction that is wider at a radially outward position and narrower at a radially inward position. The groove defines mutually facing and slanting side walls 32.

As illustrated, a support wedge 40 is provided at an upper portion of the tilt controller fitting at least partly within the tapered groove 30 of the tape spool 22.

The support wedge 40 has opposite ends 42 and 44 and extends between those ends in an arcuate shape matching the tapered groove 30 of the tape spool 22. As illustrated in Figure 5, the support wedge 40 has a cross-section matching the cross-section of the tapered groove 30. In particular, it has opposite side walls 46, which are angled so as to match the side walls 32 of the tapered groove 30. In this way, the support wedge has an arcuate extent fitting within the tapered groove 30. It is also configured so as to provide frictional engagement with the side walls 32 of the tapered groove 30.

Each respective side wall 46 of the support wedge 40 may be provided with dedicated frictional surfaces. In this respect, although a single continuous frictional surface may be provided on each side wall 46, in the illustrated embodiment, a discrete frictional surface 48a, 48b is provided towards each respective end 42, 44 of the support wedge 40.

As illustrated, the flexible support 16 is connected to the support wedge and extends from the support wedge around either side of the tape spool 22. A connection 50 is provided for connecting the flexible support 16 to the support wedge 40. This connection 50 may be of any known or convenient type. The illustrated flexible support 16 includes respective ends 16a, 16b, which meet at the connection 50. However, it is also possible for the flexible support 16 to be continuous through the connection 50.

In the illustrated embodiment, each end 16a, 16b of the flexible support 16 is provided with a mounting component, such as a bead or ball, which is secured

permanently to the respective end 16a, 16b of the flexible support 16. The illustrated connection 50 includes respective recesses 54, 56 into which the mounting portions 52 are received. In particular, the recesses 54, 56 securely hold the mounting portions 52 whilst allowing the flexible support 16 to extend from the support wedge 40. Although illustrated with respective recesses 54 and 56, the connection 50 could instead include a single recess for receiving both mounting portions 52. The support wedge 40 has an inner side facing the tape spool and an outer side facing away from the tape spool. In the illustrated embodiment, the connection 50 is provided on the outer side of the support wedge 40. This is convenient for assembly and avoids any difficulties with regard to the connection 50 interfering with the interface between the support wedge 40 and tapered groove 30. Nevertheless, it is also possible for a connection to be provided on the inner side of the support wedge 40.

As will be explained in greater detail below, where the flexible support 16 extends away from the connection 50 and around the tape spool 22, it extends at a position between the support wedge 40 and the tape spool 22. In the illustrated embodiment, this is achieved by the provision of respective throughholes between the outer side and the inner side of the support wedge 40. In particular, the throughholes allow the flexible support 16 to extend from the connection 50 at the outer side of the support wedge 40 through the thickness of the support wedge 40 to the bottom of the tapered groove 30. In this way, the support wedge 40 has a circumferential extent that extends beyond the flexible support 16. The flexible support 16 does not extend around the outer side of the support wedge 40, but, instead, travels around an inner side of the support wedge 40.

In the illustrated embodiment, the throughholes from the outer side to the inner side of the support wedge 40 are provided as complete cut-outs, which extend from the respective opposite ends of the support wedge 40. In other words, the side walls 46 of the support wedge 40 extend circumferentially beyond the position at which the flexible support 16 extends from the outer side of the support wedge 40 to the inner side of the support wedge 40.

By providing the throughholes as complete cut-outs or slots, it also becomes possible for the angle at which the flexible support 16 traverses the thickness of the support wedge 40 to vary as the tape spool 22 and support wedge 40 are rotated. In the illustrated embodiment, the tape spool 22 is provided with an additional circumferential groove 60 about which a lift cord 18 may be wound or unwound with rotation of the tape spool 22.

The lower portion 26 of the housing includes at least one aperture through which the flexible support 16 extends and at least one other aperture 62 through which a lift cord 18 may extend.

In operation, the tilt controller operates as follows.

When the tape spool 22 is rotated so as to wind or unwind a lift cord 18, the support wedge 40 is frictionally engaged with the tapered groove 30 of the tape spool 22. Hence, the support wedge 40 rotates with the tape spool 22, thereby raising the portion of the flexible support 16 on one side, and lowering the portion of the flexible support 16 on the other side, so as to tilt the suspended blind slats 14.

By providing a stop for the support wedge 40 at a particular angular position so as to prevent further rotation of the support wedge 40, further tilting of the blind slats 14 can be prevented. However, the tape spool 22 can be rotated further by overcoming the frictional engagement, thereby allowing further winding or unwinding of the lift cord 18.

With regard to the frictional engagement between the support wedge 40 and the tape spool 22, it is important that the flexible support 16 is able to extend between the support wedge 40 and the tape spool 22, in particular along the inside of the support wedge 40.

Figure 6(a) illustrates schematically the situation where a flexible support 16 extends around the outside of a support wedge, whereas Figure 6(b) illustrates schematically the embodiment of Figure 4 where the flexible support 16 extends through the thickness of the support wedge 40 to the inside of the support wedge 40 and between the support wedge 40 and the tape spool 22. With the arrangement of Figure 6(a), when the blind slats are approaching their fully tilted orientation, most of the weight exerted by the blind slats is carried by the flexible support pulling the blind slats up (on the left as illustrated) so that the support wedge is biased so as to rotate back to a less tilted position. The force of frictional engagement between the support wedge and the tapered groove must be sufficient to withstand this force from the flexible support. With the arrangement illustrated in Figure 6(a) with the flexible support running over the support wedge, the flexible support (on the left) creates a torque in a counter-clockwise direction (as illustrated), which tends to lift the wedge slightly out of the tapered groove of the tape spool so as to reduce the frictional engagement and the efficiency of the system. In practice, it is likely that the support wedge starts to slip relative to the tape spool before the blind slats reach their fully tilted (for instance closed) orientation. Thus, it becomes impossible to use the covering in the intended manner.

According to the present invention, and as illustrated in Figure 6(b), the flexible support extends through the thickness of the support wedge to the inside of the support wedge and between the support wedge and the tape spool. As a result, the weight of the blind slats causes the flexible support to load the support wedge at a different pulling angle and position, thereby creating a torque in a clockwise direction (as illustrated) and enhancing the frictional engagement force between the support wedge and the tape spool. As a result, there is a better grip between the support wedge and the tape spool and it becomes possible more securely to fully tilt or close the blind slats.

Of course, it is still necessary for the frictional engagement between the flexible support 40 and the tape spool 22 to be released at the fully tilted position so as to enable the tape spool 22 to continue rotation for winding or unwinding the lift cord 18. For this reason, as mentioned above, a stop 70 is provided in the tilt controller. The tilt stop 70 is mounted at least adjacent the outer circumference of the tape spool 22 so as to be able to engage with the respective ends 42, 44 of the support wedge 40. In the illustrated embodiment, like the support wedge 40, the tilt stop 70 is mounted so as to extend within the tapered groove 30. The tilt stop 70 is secured so as not to rotate with the tape spool 22 and is, for example, mounted securely to the lower portion 26 of the housing. The tilt stop extends between two ends, each including an end stop spaced along the circumference of the tape spool 22 and for engagement with a respective

corresponding opposite end 42, 44 of the support wedge 40. In particular, as illustrated in Figure 7, the tilt stop 70 includes a first end stop 72 for engagement with a first end 42 of the support wedge 40 and a second end stop 74 for engagement with the second end 44 of the support wedge 40.

In operation, as explained above, the tape spool 22 is rotated and the support wedge 40 is also rotated by virtue of the frictional engagement. However, at a particular angular orientation defined by the tilt stop 70, either the end 42 of the support wedge 40 will engage with the end stop 72 of the tilt stop 70 or the end 44 of the support wedge 40 will engage with the end stop 74 of the tilt stop 70. Further rotation of the support wedge 40 will thus be prevented. By overcoming the frictional engagement between the support wedge 40 and the tape spool 22, the tape spool 22 is able to rotate further in order to wind or unwind the lift cord 18 whilst the blind slats 14 remain in their fully tilted orientation.

In the illustrated embodiment, the relative positions and angles of the support wedge end 42 and end stop 72, and also the support wedge end 44 and end stop 74, are arranged such that engagement between the ends 42, 44 and tilt stops 72, 74 result in the support wedge 40 being lifted outwardly from the tapered groove 30. In this way, at the point of maximum tilt for the blind slats 14 as defined by the extent of the tilt stop 70, frictional engagement is relieved so as to help rotation of the tape spool relative to the support wedge 40. A selection of different tilt stops may be provided for use in the tilt controller 20, the tilt stops having different respective sizes, in particular with different angular extents around the circumference of the tape spool 22. The tilt stop 70 may be interchangeable with any of the tilt stops of different sizes. In this way, it is possible to accommodate different closure angles of slats or different slat widths merely by replacing the tilt stop 70.

Claims

1. A covering for an architectural opening including a head rail with a tilt controller for controlling a tilt of blind slats suspended from the head rail, the tilt controller including:

the flexible support extends from the connection and between the support wedge and the tape spool.

2. A covering according to claim 1 wherein the support wedge includes an inner side facing the tape spool and an outer side opposite the inner side and the flexible support extends from the connection along the inner side.

3. A covering according to claim 2 wherein the connection is provided on the outer side of the support wedge and the support wedge defines, on either side of the connection, throughholes between the outer side and the inner side, the flexible support extending from the connection in opposite directions through the respective throughholes.

4. A covering according to claim 1 , 2 or 3 wherein the connection is located substantially centrally between the opposite ends of the support wedge.

5. A covering according to any preceding claim wherein the flexible support includes a first end and a second end, both connected to the support wedge at the connection, the flexible support extending from the first end around one diametric side of the tape spool and extending from the second end around the opposite diametric side of the tape spool.

6. A covering according to claim 5 wherein the first end and the second end include respective beads and the connection includes a mounting portion for receiving and securing the respective beads so as to connect the first end and the second end to the support wedge.

7. A covering according to any preceding claim wherein the arcuate extent of the support wedge is between 30 degrees and 200 degrees, preferably between 140 degrees and 180 degrees.

8. A covering according to any preceding claim wherein the support wedge includes a pair of oppositely facing side walls for fitment within the tapered groove, each of the side walls having respective frictional surfaces for frictional engagement with the tapered groove.

9. A covering according to claim 8 wherein each side wall includes a respective frictional surface proximate each opposite end of the support wedge.

10. A covering according to any preceding claim wherein the tilt controller further includes one of a plurality of tilt stops of different respective sizes, the tilt stop being mounted adjacent the outer circumference of the tape spool and having end stops at opposite respective ends spaced along the circumference of the tape spool and for engagement with corresponding opposite ends of the support wedge, each end stop configured to lift the corresponding opposite end of the support wedge from the tapered groove so as to release frictional engagement between the support wedge and the tape spool such that the spacing between the end stops defines an extent of angular movement by which the tape spool is able to move the support wedge.

1 1. A covering according to claim 10 further including another tilt stop of the plurality of tilt stops, the spacing between opposite respective ends of said another tilt stop being different from the spacing between opposite respective ends of said one tilt stop so as to define a different extent of angular movement.

12. A covering according to any preceding claim wherein the head rail includes a rotatable winding shaft for selectively winding and unwinding at least one lift cord for raising and lowering the blind slats and wherein the tape spool is rotated with the winding shaft.

13. A covering according to any preceding claim including a plurality of said tilt controllers spaced along said head rail.

14. A covering according to any preceding claim further including a plurality of blind slats, each blind slat having respective opposite edges supported by the flexible support for tilting and untilting the blind slats.

15. A method of controlling tilting of suspended blind slats of a covering using a flexible support supporting opposite respective edges of the blind slats, the method including: