EP2975207B1

EP2975207B1 - A screening arrangement with improved cord tightening means

Info

Publication number: EP2975207B1
Application number: EP15170309.7A
Authority: EP
Inventors: Lone Ejbaek Meyer
Original assignee: VKR Holding AS
Current assignee: VKR Holding AS
Priority date: 2014-06-02
Filing date: 2015-06-02
Publication date: 2017-04-19
Anticipated expiration: 2035-06-02
Also published as: EP2975207A1; PL2975207T3

Description

The present invention relates to a screening arrangement for a window, in particular a roof window, having a supply condition and a condition of use, the screening arrangement defining, in the condition of use, a first longitudinal direction, and a second longitudinal direction, and a screening plane substantially parallel to a plane defined by the first and second directions, the screening arrangement comprising: at least one operating element extending in the first direction between a first end and a second end and being movable in the second direction, a screening body extending, in the condition of use, substantially in the screening plane between the two operating elements; at least one cord system including a number of cords routed along the at least one operating element and having a pre-defined total length, and at least one cord tightening device connected to the at least one operating element and providing a detour length. The invention furthermore relates to a window frame comprising a screening arrangement.
Such screening arrangements including screening devices in the form of blinds are traditionally used for screening an aperture of a building structure, most often the light-admitting aperture of windows, but also of doors and other building openings. The blinds are either installed to extend substantially vertically in a building façade, as in an obliquely positioned roof window installed in an inclined roof surface, or as a horizontally extending cover for openings in a horizontal surface. When not screening the aperture, the screening body is normally folded up and gathered at a top element, or, when the screening arrangement includes two movable operating elements, at arbitrary positions in the window aperture, i.e. the two operating elements are distanced from the top piece and the bottom piece
It is well-known that proper tension of the cords needs to be controlled in case the screening arrangement includes a cord system for ensuring parallel guidance and/or holding of the operating element or elements in the desired positions. This can either be done by providing or cutting the cord to its precise length, which may be difficult, or by providing a tensioning or tightening device.
In one kind of device, proper tension is achieved by connecting the cord to pre-tensioning means such as a spring, or by making the cord itself elastic Examples of a spring-based tensioning means is shown in US 5,460,215 and EP 0 860 577 B1 . Although well-functioning and mechanically easy, a spring has a limited capacity and its characteristic deteriorates over time. Hence, it is not applicable in all fields of application, in particular when large tolerances and/or the movable parts of the screening arrangement are heavy.
This applies i.a. to screening arrangements including a so-called Roman blind. Here, the screening body is made of a flexible cloth, and the weight of the screening body may be substantial as compared to other screening arrangements.
In another kind of device, the tension of the cord is obtained by providing one or more detours of the cord, for instance shown in US 4,433,713 and US 4,557,309 , or a combination thereof, which sets out to alleviate some of the disadvantages mentioned in the above, for instance EP 1 783 318 A2 . This document could constitute the closest prior art and provides a well-functioning tensioning.
However, there is still room for improvement.
With this background it is an object to provide a screening arrangement with a cord tightening device which provides for satisfactory performance in use and which is furthermore easy to mount and does not require excess space in the operating elements.
In a first aspect of the invention, this and further objects are met by a screening arrangement of the kind mentioned in the introduction, which is furthermore characterized in that each cord tightening device comprises a base member which is stationary relative to the respective operating element and a shifter member which is movable to a plurality of positions relative to the base member to adjust the tightening of the cord by changing the detour length while retaining the pre-defined total length, in that at least one cord is routed past at least one set of turning points on the base member and the shifter member, the distance between the turning points of said at least one set being variable as a result of the relative movement between the shifter member and the base member, and in that engagement means are provided for locking the shifter member in said plurality of positions.
In this manner a very reliable operation is achieved, and which is furthermore compact as the change of the detour length takes place within the cord tightening device itself, and no additional room in the operating element in which it is mounted is needed.
Preferred embodiments of the invention are stated in dependent claims 2 to 18 and 20, respectively.
In a second aspect of the invention, a window frame comprising screening arrangement is provided as stated in claim 19.
The advantages of the first aspect of the invention and further developed embodiments are also applicable to the second aspect of the invention have been explained in the above description, and reference is made thereto.
Further details are described, and further advantages stated, in the description of particular embodiments of the invention.
In the following the invention will be described in further detail by means of examples of embodiments with reference to the schematic drawings, in which

Fig. 1 is a perspective view of a window frame with a screening arrangement in an embodiment of the invention;
Fig. 2 is a front view of a window frame with details of a screening arrangement in an embodiment of the invention;
Fig. 3 is a perspective view of details of a screening arrangement in an embodiment of the invention;
Figs 4 to 7 are perspective views, on a larger scale, of details of a screening arrangement in an embodiment corresponding to Figs 2 and 3;
Figs 8 to 11 are partial perspective views of details of an embodiment of a screening arrangement in a supply condition;
Fig. 12 shows a perspective view of the details of Figs 8 to 11, from another angle; and
Fig. 13 shows a plan view of the details of Figs 8 to 12.

Fig. 1 shows an embodiment of a screening arrangement 1 according to the invention mounted in a window frame generally designated 2 and representing a window. In the embodiment shown, window frame 2 is an openable sash adapted to be mounted in a stationary frame to be installed in an inclined roof surface. It is noted that the terms "sash" or "frame" is to be understood as incorporating any substantially rectangular structure positioned in any opening in a building, whether in a wall or the roof, and surrounding an aperture to be screened.
As shown in Fig. 2, the window frame 2 is substantially rectangular and has a top piece 21, two side pieces 22, 23 and a bottom piece 24. Fig. 2 also shows some components of the screening arrangement 1 in one stage of the installation process, i.e. between a supply condition and a condition of use. The screening arrangement defines, in the condition of use, a first longitudinal direction, and a second longitudinal direction, and a screening plane substantially parallel to a plane defined by the first and second directions. The longitudinal direction of the top and bottom pieces 21, 24 corresponding to a width direction of the window frame is parallel to the first direction, and the longitudinal direction of the side pieces 22, 23 corresponding to a height direction is parallel to the second direction. The terms "left-hand" and "right-hand" refer to the orientation shown in for instance Figs 1 and 2, and are utilized for reasons of convenience only. Similarly, the terms "front" and "back" are utilized to denote the sides of the screening arrangement 1, "front" being the side intended to face inwards into the interior of a building, and "back" the outwards facing side. The terms "upper" and "lower" refer to the orientation of the screening arrangement installed in a frame, where "upper" refers to the top piece of the frame and "lower" refers to the bottom piece of the frame.
In the embodiment shown, the screening arrangement 1 is a Roman blind and the screening body (not shown) is made from a flexible cloth including a number of pockets with openings, each for reception of one transverse element of said plurality of transverse elements. The screening arrangement 1 of the embodiment shown comprises two operating elements 71, 72 extending in the first direction and constituting an upper operating element 71 and a lower operating element 72. The operating elements 71, 72 are adapted to act as handles in the condition of use, during operation of the screening arrangement 1, i.e. when moving the operating elements 71, 72 and hence the screening body between a non-screening position and a screening position, in which the screening body covers the sash or frame aperture partly or fully. The operating elements 71, 72 are formed in any suitable manner, for instance as extruded profile elements of a suitable material such as aluminium. The screening body extends, in the condition of use, substantially in the screening plane between the two operating elements 71, 72.
Two side rails 8, 9 are provided, each extending, in the condition of use, in the second direction, at the left-hand and the right-hand, respectively, of side piece 22, 23 of the window frame 2. The side rails 8, 9 are formed by suitable means and materials, such as extruded profiles of aluminium and are connected to respective side pieces with fastening means such as screws and/or brackets to be described in further detail below.
As a preferred embodiment of the invention, the screening arrangement comprises a cord system comprising two cords 91, 92, one cord being adapted to extend from the left-hand lower corner of the sash, up through or along the operating elements 71, 72 and further up to the top piece 21 of the window frame 2. The other cord is routed in a mirror-inverted manner.
Eventually, Fig. 2 shows a transportation and mounting fitting 25 which acts as retaining means for the operating elements 71, 72 and the cord system in the supply condition, and also has a function during the mounting of the screening arrangement 1 in the window frame 2. The transportation and mounting fitting 25 is connected to a mounting bracket 15 fastened to the side pieces 22, 23 of the window frame 2 to hold the operating elements 71, 72 in the correct position temporarily. The mounting of the screening arrangement is the subject-matter of Applicant's co-pending application filed on the same date as the present application.
As schematically indicated in Fig. 2 and is shown in more detail in Fig. 13, cord 91 is composed of two cord portions 91 a, 91 b having at one end a cord holder block 911 for connection to the upper right-hand corner of the frame and a cord holder block 912 for connection to the lower left-hand corner. Correspondingly, cord 92 is composed of two cord portions 92a, 92b having at one end a cord holder block 921 for connection to the lower right-hand corner of the frame and a cord holder block 922 for connection to the upper left-hand corner. Although not shown in detail, it is appreciated that cord portions 91 a, 92a are routed along the upper operating element 71 and cord portions 91 b, 92b are routed along the lower operating element 72. By the term "along" is to be understood that the cords may pass through the operating element in question, or outside, for instance on the back side. In principle, cords 91, 92 may be routed along at least the side pieces 22, 23 of the window frame and the operating elements 71, 72 as deemed suitable to ensure proper functioning. For instance, a so-called "H system" or "double H system" may be provided.
At the respective operating elements 71, 72, each cord is connected with a cord tightening device which will be described in further detail below. The cord tigthening devices entail that the cords are held suitably tight all the time during use, thereby ensuring that the operating elements 71, 72 at all times are kept substantially in parallel with the top and bottom pieces of the window frame, and makes it possible to retain the operating elements 71, 72 in an arbitrary position measured in the second direction, i.e. along the side pieces 22, 23 of the window frame 2.
Although the screening arrangement of the embodiments shown comprise one screening device having two operating elements, other configurations are conceivable. For instance, there may be more than two operating elements. In principle, the invention is also applicable to screening arrangements comprising only one operating element.
In Fig. 3, the back side of the upper left-hand corner of the window frame is shown to illustrate the interaction of a cord tightening device 4 with the side rail 8 in the condition of use in one embodiment of the invention.
Referring now to the more detailed views of Figs 4 to 13, one embodiment of a screening arrangement incorporating a cord tightening device 4 which provides suitable tightening of the cords as described briefly in the above, will be described in detail. The principles underlying the present invention are described below.
As will be appreciated the cord tightening device 4 is of the kind providing a detour length. The cord tightening devices 4 of the present embodiment are connected to the operating elements 71, 72 in the supply condition.
Each cord tightening device 4 comprises a base member 41 which is stationary relative to the respective operating element 71, 72 and a shifter member 42 which is movable to a plurality of positions relative to the base member 41 to adjust the tightening of the cord by changing the detour length while retaining the pre-defined total length,
Cords 91, 92 are routed past at least one set, here two sets, of turning points 411, 421; 412, 422 on the base member 41 and the shifter member 42. By moving the shifter member 42 relative to the base member 41, the distance between the turning points is varied and the length of the detour is increased or decreased. In the embodiment shown, there are two sets of turning points, viz. a first set of turning points 411, 421 and a second set of turning points 412, 422, but embodiments are conceivable having only one set of turning points.
Once the proper cord tightening has been achieved, engagement means 415, 425 provided for locking the shifter member 42 in the desired position are allowed to enter into mutual engagement.
In the specific embodiment, each turning point is provided as a substantially L protrusion forming a cleat 411, 421; 412, 422 on the base member 41 and the shifter member 42, respectively. The provision of T-shaped protrusions is conceivable
The base member 41 comprises a substantially plate-shaped main portion 410 with two end edges and two side edges, and one cleat 411 of the first set of turning points is provided at or near one end edge, and another cleat 412 of a second set of turning points is provided at or near the opposite end edge.
The shifter member 42 comprises a substantially plate-shaped main portion 420 with two end edges and two side edges, and one cleat 421 of a first set of turning points is provided at or near one end edge, and another cleat 422 of a second set of turning points is provided at or near the opposite end edge.
Each cleat 411, 421; 412, 422 is substantially L-shaped, with the openings 411 a, 412a of the cleats 411; 412 of the base member 41 and the openings 421a, 422a of the cleats 421; 422 of the shifter member 42 face away from each other in each of the sets.
The base member 41 and the shifter member 42 may be formed in any suitable manner, for instance as moulded parts of a suitable plastic material.
The locking is provided by positive engagement, i.e. formlocking engagement, which provides a more reliable engagement than for instance non-positive engagement such as for instance friction. In the embodiment shown, the engagement means comprise a first toothing 415 on the base member 41 adapted to cooperate with a corresponding second toothing 425 on the shifter member 42. In order to ease tightening of the cords, the first toothing 415 and/or the second toothing 425 are asymmetrical.
The actual adjustment, i.e. the moving of the shifter member 42 to the position providing the desired cord tightening, the shifter member 42 is provided with an adjustment fin 427 connected to the main portion 420 and protruding through a longitudinal adjustment slot 417 in the main portion 410 of the base member 41, the adjustment fin 427 being as here provided with an opening 427a surrounded by two flanges 427b to ease operation. As shown in Fig. 3, the adjustment fin 427 protrudes from the operating element 71 in that the operating element 71 is here formed with a track 71a which is open towards the back of the screening arrangement. This provides for an easy adjustment while at the same time being inconspicuous in the condition of use.
Guidance of the shifter member 42 relative to the base member 41 in the longitudinal direction is foreseen in that the shifter member 42 is provided with a longitudinal guide slot 424 for cooperation with a guide surface 414 at the first cleat 411.
Furthermore, the shifter member 42 is provided with a tail portion 426 adapted to be in contact with a shoulder portion 416 of the base member 41 in one end position of the shifter member 42 relative to the base member 41, the base member 41 being preferably provided with a stop surface 413 adapted to be in contact with one end edge 423 of the shifter member 42 in said one end position.
The base member 41 is provided with a multi-purpose end guide 418 at one end wall 419 of the base member 41 including a set of guide apertures 418a, 418b adapted to receive a corresponding cord 91, 92. Here, the cords 91, 92 are routed on either side of a dividing wall 408, but embodiments are conceivable where the cords are just routed out through a single aperture.
As indicated also in Fig. 3, the screening arrangement includes two side rails 8, 9, each extending, in the condition of use, in the second direction, and the end guide 418 is shown also in Fig. 3. The guiding in the side rails takes place in that the end guide 418 further includes a guide track 418c adapted to cooperate with a corresponding track in the side rails 8, 9.
In the supply condition, the cord tightening device 4 is preferentially already inserted into the respective operating element 71, 72. In the case in which each operating element is provided as a profile, for instance by extruded aluminium, with tracks for reception of the cord tightening devices, cord tightening devices 4 are introduced through the ends of the operating elements 71, 72. To that end the base member 41 and the shifter member 42 comprise means for sliding engagement with the operating element 71, 72. The sliding engagement means may be provided on one of the base member 41 and the shifter member 42 only.
In the specific embodiment, the sliding engagement means comprise a track portion 406 formed between the main portion 410 and a first raised platform 407 of the base member 41, preferably flush with a track portion formed between the main portion 420 and a stepped section 420a of the shifter member 42. The end wall 419 forms a stop for the sliding movement, thus specifying the exact position of the end guide 418 cooperating with the side rails.
Furthermore, the sliding engagement means comprise in the embodiment a second raised platform 409 on the base member 41 and a resilient tongue 428 on the shifter member 42, preferably as here formed at the cleat member 422 of the second set of the shifter member 42.
Indicated in Figs 8 to 11 is an embodiment of the transportation and mounting fitting 25 which is releasably connected to the operating elements 71, 72 in the supply condition, and each fitting 25 includes hook means 258, 259 for holding said cords 91, 92 temporarily, and optionally also for cord holder blocks 911, 912, 921, 922. The hook means include two hook portions 258, 259 provided on the main portion 251 with hook openings facing each other.
The base member 41 may also be used alone without the shifter member 42 and then functions as an end member providing guidance in the side rails and ensures that smooth guidance of the cords 91, 92 is provided. This is the case in the present embodiment, in which one base member 41 is connected to each end of each operating element 71, 72 and one shifter member 42 is connected to one of the two base members 41 of each operating element 71, 72.
The pre-defined total length of the cords 91, 92 is defined by the dimensions of the window frame 2, i.e. width and height, to match for instance specific sizes within a size range. Tolerances in the window frame, cords etc. are compensated for by setting the cord tightening devices 4 in the proper position.

Claims

A screening arrangement (1) for a window, in particular a roof window, having a supply condition and a condition of use, the screening arrangement defining, in the condition of use, a first longitudinal direction, and a second longitudinal direction, and a screening plane substantially parallel to a plane defined by the first and second directions, the screening arrangement comprising:
at least one operating element (71, 72) extending in the first direction between a first end and a second end and being movable in the second direction,

a screening body extending, in the condition of use, substantially in the screening plane;

at least one cord system including a number of cords (91, 92) routed along the at least one operating element (71, 72) and having a pre-defined total length, and

at least one cord tightening device (4) connected to the at least one operating element (71, 72) and providing a detour length,

characterized in that

each cord tightening device (4) comprises a base member (41) which is stationary relative to the respective at least one operating element (71, 72) and a shifter member (42) which is movable to a plurality of positions relative to the base member (41) to adjust the tightening of the cord by changing the detour length while retaining the pre-defined total length,

in that at least one cord (91, 92) is routed past at least one set of turning points (411, 421; 412, 422) on the base member (41) and the shifter member (42), the distance between the turning points of said at least one set being variable as a result of the relative movement between the shifter member (42) and the base member (41), and

in that engagement means (415, 425) are provided for locking the shifter member (42) in said plurality of positions.
A screening arrangement according to claim 1, wherein two sets of turning points (411, 421; 412, 422) are provided.
A screening arrangement according to claim 1 or 2, wherein each turning point is provided as a substantially L or T-shaped protrusion forming a cleat (411, 421; 412, 422) on the base member (41) and the shifter member (42), respectively.
A screening arrangement according to claim 3, wherein the base member (41) comprises a substantially plate-shaped main portion (410) with two end edges and two side edges, and wherein one cleat (411) of a first set of turning points is provided at or near one end edge, and another cleat (412) of a second set of turning points is provided at or near the opposite end edge.
A screening arrangement according to claim 3 or 4, wherein the shifter member (42) comprises a substantially plate-shaped main portion (420) with two end edges and two side edges, and wherein one cleat (421) of a first set of turning points is provided at or near one end edge, and another cleat (422) of a second set of turning points is provided at or near the opposite end edge.
A screening arrangement according to claim 4 and 5, wherein each cleat (411, 421; 412, 422) is substantially L-shaped, with the openings (411 a, 412a) of the cleats (411; 412) of the base member (41) and the openings (421 a, 422a) of the cleats (421; 422) of the shifter member (42) face away from each other in each of said sets.
A screening arrangement according to any one of the preceding claims, wherein the engagement means comprise a first toothing (415) on the base member (41) adapted to cooperate with a corresponding second toothing (425) on the shifter member (42).
A screening arrangement according to claim 7, wherein the first toothing (415) and/or the second toothing (425) is/are asymmetrical.
A screening arrangement according to any one of claims 4 to 8, wherein the shifter member (42) is provided with an adjustment fin (427) connected to the main portion (420) and protruding through a longitudinal adjustment slot (417) in the main portion (410) of the base member (41), the adjustment fin (427) being preferably provided with an opening (427a) surrounded by two flanges (427b).
A screening arrangement according to any one of claims 4 to 9, wherein the shifter member (42) is provided with a longitudinal guide slot (424) for cooperation with a guide surface (414) at the first cleat (411).
A screening arrangement according to any one of claims 4 to 10, wherein the shifter member (42) is provided with a tail portion (426) adapted to be in contact with a shoulder portion (416) of the base member (41) in one end position of the shifter member (42) relative to the base member (41), the base member (41) being preferably provided with a stop surface (413) adapted to be in contact with one end edge (423) of the shifter member (42) said one end position.
A screening arrangement according to any one of claims 4 to 11, wherein the base member (41) is provided with a multi-purpose end guide (418) at one end wall (419) of the base member (41) including a set of guide apertures (418a, 418b) adapted to receive a corresponding cord (91, 92).
A screening arrangement according to claim 12, wherein the screening arrangement includes two side rails (8, 9), each extending, in the condition of use, in the second direction, and the end guide (418) further includes a guide track (418c) adapted to cooperate with a corresponding track in the side rails (8, 9).
A screening arrangement according to any one of the preceding claims, wherein the base member (41) and/or the shifter member (42) comprise means for sliding engagement with the at least one operating element (71,72).
A screening arrangement according to any one of claims 4 to 13 and 14, wherein the sliding engagement means comprise a track portion (406) formed between the main portion (410) and a first raised platform (407) of the base member (41), preferably flush with a track portion formed between the main portion (420) and a stepped section (420a) of the shifter member (42).
A screening arrangement according to any one of claims 4 to 13 and 14 or 15, wherein the sliding engagement means comprise second raised platform (409) on the base member (41) and a resilient tongue (428) on the shifter member (42), preferably formed at the cleat member (422) of the second set of the shifter member (42).
A screening arrangement according to any one of the preceding claims, wherein at least one fitting (25) is releasably connected to the at least one operating element (71, 72) in the supply condition, and each fitting (25) includes hook means (258, 259) for holding said cords (91, 92) temporarily, and optionally for cord holder blocks (911, 912, 921, 922).
A screening arrangement according to any one of the preceding claims, wherein one base member (41) is connected to each end of the at least one operating element (71, 72) and one shifter member (42) is connected to one of the two base members (41) of the respective operating element (71, 72).
A window frame comprising a screening arrangement according to any one of claims 1 to 18, wherein the window frame (2) includes a top piece (21), two side pieces (22, 23) and a bottom piece (24), and the longitudinal direction of the top and bottom pieces (21, 24) corresponding to a width direction of the window frame is parallel to the first direction, and the longitudinal direction of the side pieces (22, 23) corresponding to a height direction is parallel to the second direction, and wherein the pre-defined total length is defined by the dimensions of the window frame.
A window frame according to claim 19, wherein the screening arrangement comprises two operating elements constituting an upper operating element (71) and a lower operating element (72), and wherein each cord (91, 92) is composed of two cord portions (91 a, 91 b, 92a, 92b) having at one end a cord holder block (911, 922) for connection to the upper right-hand and left-hand corner, respectively, of the window frame and a cord holder block (912, 921) for connection to the lower left-hand and right-hand corner, respectively, one set of cord portions (91 a, 92a) being routed through the upper operating element (71) and another set of cord portions (91 b, 92b) being routed through the lower operating element (72).