WO2006074653A1

WO2006074653A1 - A winding device for a cord guidance system of a screening device for the screening of a window

Info

Publication number: WO2006074653A1
Application number: PCT/DK2005/000011
Authority: WO
Inventors: Martin Armand Mortensen
Original assignee: Vkr Holding A/S
Priority date: 2005-01-11
Filing date: 2005-01-11
Publication date: 2006-07-20
Also published as: EP1836371B1; EP1836371A1; PL1836371T3; CN101099022A

Abstract

The winding device (1a, 1b) is meant for a cord guidance system of a screening device for the screening of a window. It comprises a winding reel (1c, 1d) with a rotational axis, the winding reel comprising a circumferential abutment or rewinding surface (7) with two ends, the rewinding surface being sunk between two end guides (21, 22) located perpendicular to said axis at said ends of said rewinding surface. The rewinding surface comprises a cord track (7a) threaded in the rewinding surface for winding a cord (8, 9) in a first, inner layer on said winding reel. Furthermore, the winding device comprises a cord guidance means separate from the winding reel for winding the cord in a second, outer layer on the winding reel.

Description

A winding device for a cord guidance system of a screening device for the screening of a window

The present invention relates to a winding de- vice for a cord guidance system of a screening device for the screening of a window, the winding device comprising a winding reel with a rotational axis , said winding reel comprising a rewinding surface sunk between two end guides located substantially perpen- dicular to said rotational axis at the ends of said rewinding surface .

Winding devices of this type are known in the art and are used in screening devices of the type comprising a screening body which is movable in a longitudinal direction of a window parallel to the plane of the window between a first end position in which it occupies a rolled-up, pleated or folded position at one of the top and bottom frame or sash members of the window and a second, active end posi- tion in which for the screening of the window, it is extended between said top and bottom frame or sash members . The movement of the screening body from the first to the second end position is obtained by a cord guidance comprising two cords , each in one end being connected to a winding device at one of said frame or sash members, and in the other end being connected to a bottom bar, the cords being spring- loaded at their respective other ends . At the sides of the window the cords are guided in guide rails . Examples of such screening devices are described in e . g . WO 02/06621 Al , EP-Bl-O 804 674 and DK 174 398 Bl .

Such screening devices are known in many forms and comprise e .g . awning blinds , roller blinds and roller shutters , where the screening body in the non- screening position is rolled-up on a reception means in the form of a roller . In screening devices of this type, the winding reels are usually located in a top box at the ends of the roller . The winding of the cord on the rewinding surface of the winding reel is normally obtained by winding of the cord in several cord layers on the winding reel . However, during winding of the cord, one or more windings of an upper cord layer may suddenly fall down between the windings of a lower cord layer, resulting in the forming of knots and a more difficult winding of the cord, and/or a disturbing, loud noise that may be per- ceived, by the user, as a malfunction of the screening device .

As is described in DK 174398 Bl , one solution to these problems would be to wind the cord in a single layer. This solution entails , however, equally significant problems since the winding reel must be provided with a corresponding, large width. In many situations , e . g . if two or more windows are to be placed next to one another in the immediate proximity of each other, only a limited winding reel space is available at each side of the window. In order to reduce the accumulated width of the screening device, the winding reels are often offset inwards with respect to the guiding of the cords at the sides of the window sash. Usually, the width of the winding reel thus determines the greatest width of a screening body that may be used with the current window. The cause of this is the position of the winding reel in the top box of the screening device , occupying part of the roller . Thus, the offset of the winding reels makes it difficult and often impossible to provide a screening body wide enough to completely cover the aperture of the window. In many cases , e .g . in the case of a blackout screening, such an inadequate screening is a significant drawback.

Also, when the cord is wound on a wide winding reel , the guide rails at the sides of the window must be provided with an equivalent width so that the cord may be wound on the reel by means of an oscillating movement from side to side . As a result , the guide rails will often proj ect over the window aperture, decreasing the view through the window and, particularly in the case of outside mounting of the screen- ing device, providing the window with an unpleasant appearance . The width of the guide rails may be reduced by providing a guiding device in the form of e . g . an auxiliary reel at the winding reel . This , however, complicates and raises the production costs of the screening device .

It is an obj ect of the present invention to provide a winding device of the type mentioned in the introduction, which provides for a reliable and smooth winding up of a screening body of a screening device and, at the same time, takes up a sufficiently small amount of space in the lateral direction of the screening device in order to rectify or lessen the above-mentioned problems .

To meet this obj ect the winding device accord- ing to the invention is characterized in that said rewinding surface comprises a cord track threaded in said rewinding surface for winding a cord in a first , inner layer on said winding reel , and said winding device further comprises a cord guidance means separate from said winding reel for winding said cord in a second, outer layer on said winding reel .

The combination of a cord track and a separate cord guidance means provides for a controlled, tight winding of the cord in layers on the winding reel and an optimum solution regarding space taken up by the windings . In this connection, the word " separate" is to be understood in the sense that the cord guidance means is not ' fixed ' to the rotating rewinding surface of the winding reel . The cord may be wound up completely in two layers on a winding reel with a limited width, making it possible for two adjoining windows, avoiding space problems , to both be equipped with screening devices comprising the winding device according to the invention. Further, the tight winding of the cord solves the problems regarding a cord section from an upper layer falling to a lower layer . In an advantageous embodiment of the invention said cord guidance means comprises a guiding surface located substantially parallel to said rotational axis , opposed to and spaced apart from said rewinding surface of said winding reel . The guiding surface may e . g . be provided on a curved panel . These features provide for a reliable guidance of the cord and avoid wear of the cord .

Advantageously, said guiding surface is slightly inclined in the cord rewinding direction of the first layer, parallel to the rotational axis of said winding reel , whereby the guiding surface may push each winding of the second layer against a previous winding, ensuring a tight winding of the cord.

Preferably, said winding reel and said guiding surface are integrated in a reel house, such a house strengthening the general construction of the winding device and being cheap in manufacture .

In another embodiment , a screening device for the screening of a window comprises a screening body movable in a longitudinal direction of the window parallel to the plane of the window between a first end position in which it occupies a rolled-up, pleated or folded position at one of the top and bot- torn frame or sash members of the window and a second, active end position in which for the screening of the window, it is extended between said top and bottom frame or sash members, in which the movement of the screening body from said first to said second end po- sition is obtained by a cord guidance comprising at least one cord, which in one end is connected to a winding device at one of said frame or sash members, and in the other end is connected to a bottom bar or the like, the at least one cord being spring-loaded at its respective other end, in which said winding device is according to one of the above embodiments .

In an embodiment of the screening device, movement of the screening body from said first to said second end position is obtained by a cord guidance comprising two cords, each in one end being connected to a winding device at one of said frame or sash members, and in the other end being connected to a bottom bar or the like , the cords being spring-loaded at their respective other ends . In another embodiment of the screening device, the cord is wound in two and only two layers on said winding reel when said screening body is in said second end position. The invention will be explained in detail in the following by means of examples of embodiments with reference to the schematic drawing, in which

Fig . 1 is a perspective view of a screening de- vice mounted on the exterior of a standard window, the screening device comprising an embodiment of a winding device according to the invention,

Fig. 2 is a cross section through the winding device of the screening device according to Fig . 1 in more detail , and

Fig . 3 is a perspective view of a detail of the winding device seen from the right in Fig . 1.

Fig . 1 is a view of an embodiment of a screening device with two winding devices Ia, Ib according to the invention. The screening device is an external awning blind with a screening body in the form of an awning cloth 2 which in one end is fastened to a roller 3 constituting a reception means for the screening body and mounted in a top casing 4 at the top frame member of the window. The opposite free end of the awning cloth 2 is connected to a tubular bottom bar 5.

The screening device further comprises a side guide rail (not shown) on each side of the window, the guide rails in a mounted position being connected to the side members of the sash structure . The side guide rails accommodate and lead the ends of the bottom bar 5 and the edges of the awning cloth 2. The awning cloth 2 is shown in an extended position sub- stantially covering the window aperture 6.

For movement of the bottom bar 5 and the connected end of the awning cloth 2 from a first end position in which the bottom bar 5 is positioned at or in the top casing 4 such that the window is not screened by the awning cloth 2 , to a second end position in which the bottom bar 5 is positioned at the bottom frame or sash member of the window, the bottom bar 5 is connected to a cord guidance comprising two cords 8 and 9 which are led each in their side guide rail .

Referring now also to Figs 2 and 3 , the winding devices each comprise a reel house 15 , a winding reel Ic , Id and a cord guidance means in the form of a curved panel 11 supported by two supports 13 , 14. Each cord 8 and 9 is in one end fastened to their respective winding reel Ic and Id, which in the shown design are placed on each end of the roller 2. The winding reels Ic and Id are coupled to an electric drive unit in the form of an electric motor (not shown) with an associated transmission such that the displacement of the bottom bar 5 from the first to the second end position is effected by electric op- eration of a keyboard designed for this purpose, perhaps a remote control . The electric motor may e . g . be in the form of a small motor device located inside the roller 3 , the roller being provided e . g . as a hollow, tubular member. From the winding reels Ic, Id, each cord 8 , 9 is through the associated side guide rail led around a cord return element e . g . in the form of a pulley 17 , 18 placed at the bottom frame or sash member and into one and the other, respectively, end of the tu- bular bottom bar 5 , where the free cord end is connected to one end of a screw compression spring 19 , 20 , the other end of said spring 19 , 20 being connected to the bottom bar 5 in the same side . Figs 2 and 3 show the winding device Ia of Fig . 1 in more detail . The winding reel Ic is designed with a circumferential abutment or rewinding surface 7 for the cord rewinding in order to assure the re- winding of the cord 8 on the associated winding reel Ic in a first , tightly packed layer of cord windings, the rewinding surface 7 comprising a cord track in the form of a thread 7a . The threading of the thread 7a may be given a semi-elliptical shape in order to accommodate the compression of the cord 8 against the rewinding surface 7 during rewinding of the cord 8 , the optimum shape of the threading depending on the hardness of the cord 8.

The panel 11 has a guiding surface 12 located substantially parallel to the rotational axis of the winding reel Ic, opposed to and spaced apart from the rewinding surface 7 of the winding reel Ic and is fixed in relation to the winding reel Ic in order to assure the rewinding of each cord 8 on the winding reel Ic in a second layer of cord windings .

In the shown embodiment , the rewinding surface 7 of the winding reel Ic is sunk between two end guides 21 , 22 , and the associated cord 8 is fastened to the winding reel Ic at one end guide 22 , whereas the cord guide 21 is designed as a disk element positioned opposite the rewinding surface 7. The reel h,ouse 15 is located at one end of the top casing 4.

During rotation of the winding reels Ic, Id, the bottom bar 5 will be displaced from the first to- wards the second end position. During this displacement, each cord 8 and 9 will , as a consequence of the spring load from the screw compression springs 19 , 20 , be kept tightly extended. As is seen best from Fig . 3 , in order to rewind the cord 8 , the cord 8 is initially led across the guiding surface 12 , after which it is wound up, from one end guide 21 to the other 22 , in an inner layer, guided by the thread 7a on the winding reel Ic . When the cord 8 reaches the end guide 22 , the winding is reversed and continues in the opposite direction, forming a second cord layer . The windings of the second layer are wound tightly packed against the first layer and each other because of the spring load from the screw compression springs 19, 20 in combination with the influence of the panel 11. When the cord 8 once more reaches the end guide 21 , the bottom bar 5 will be in its second end position; this is the situation shown in Fig. 2. The winding of the cord 9 on the winding reel Id is analogous to the winding of the cord 8 on the winding reel Ic .

As shown in Fig . 3 , the winding device Ia further comprises two supports 13 , 14 integrated in and supporting the panel 11 against the reel house 15. In the embodiment shown, the reel house 15 encloses the panel 11 , the supports 13 , 14 and the reel Ic₇ the reel house 15 , panel 11 and supports 13 , 14 being manufactured from a plastics material and cast in one piece . In consideration to the draught angle of the casting process, the panel 11 and thus the guiding surface 12 are slightly inclined in a direction parallel to the rotational axis of said winding reel against the end guide 22. This provides the advanta- geous side effect that the cord windings of the second layer are pressed even tighter against the previous windings of said layer . Depending on the design of the winding device , this inclination of the guid- ing surface may not be necessary since a previous winding of the cord 8 may push or urge the next winding into place next to the previous winding .

Referring again to Fig . 1 , instead of being po- sitioned in the top casing 4 , the winding reels Ic, Id may along with the associated electric drive unit be arranged in a bottom casing at the bottom frame or sash member of the window, which may entail the advantage that the length of the winding cords 8 , 9 may be shortened such that the width of the winding reels Ic , Id can be further reduced.

In an embodiment as shown in the drawings, the movement of the screening body 2 in the opposite direction may be effected by impact from the roller by a constant force, e .g . a spring force, or electrically by means of a separate rewinding motor.

Even though the invention in the above has been described only for an external awning blind as an embodiment example, it may also be used in other cur- rent forms of screening arrangements such as roller shutters .

Further, the cords 8 , 9 may be wound up on the winding reels Ic, Id, respectively, in more than two layers , e .g . three or four layers . Also, the - guiding surface may be provided in any other suitable way, such as part of a recess in a panel , or a pin as e . g . shown in WO 02/06621.

Claims

P A T E N T .C L A I M S

1. A winding device (Ia, Ib) for a cord guidance system of .a screening - device for the screening of a window, the winding device (Ia, Ib) comprising a winding reel (Ic , Id) with a rotational axis , said winding reel (Ic , Id) comprising a circumferential abutment or rewinding surface (7) with two ends , said rewinding surface (7) being sunk between two end guides (21 , 22 ) located substantially perpendicular to said rotational axis at said ends of said rewinding surface (7) , c h a r a c t e r i z e d in that said rewinding surface (7) comprises a cord track (7a) threaded in said rewinding surface (7) for winding a cord (8 , 9) in a first , inner layer on said winding reel (Ic , Id) , and said winding device (Ia, Ib) further comprises a cord guidance means separate from said winding reel (Ic , Id) for winding said cord ( 8 , 9) in a second, outer layer on said winding reel (Ic , Id) .

2. A winding device (Ia, Ib) according to claim

1 , c h a r a c t e r i z e d in that said cord guidance means comprises a guiding surface (12 ) located substantially parallel to said rotational axis , opposed to and spaced apart from said rewinding surface (7) of said winding reel (Ic, Id) .

3. A winding device (Ia, Ib) according to claim

2 , c h a r a c t e r i z e d in that said guiding surface (12 ) is provided on a curved panel (11) .

4. A winding device according to claim 2 or 3 , c h a r a c t e r i z e d in that said guiding surface (12 ) is slightly inclined in the cord rewinding direction of the first layer, parallel to the rota- tional axis of said winding .reel (Ic , Id) .

5. A winding device (Ia, Ib) according to one of • claims 1 to ^' 4 , c h a . r a c t^" e r . i z e d ^' in that said winding reel (Ic, Id) and said cord guidance means are integrated in a reel house (15) .

6. A screening device for the screening of a window, comprising a screening body (2 ) movable in a longitudinal direction of the window parallel to the plane of the window between a first end position in which it occupies a rolled-up, pleated or folded position at one of the top and bottom frame or sash members of the window and a second, active end position in which for the screening of the window, it is extended between said top and bottom frame or sash members , in which the movement of the screening body (2 ) from said first to said second end position is obtained by a cord guidance comprising at least one cord ( 8 , 9) , which in one end is connected to a wind- ing device (Ia, Ib) at one of said frame or sash members , and in the other end is connected to a bottom bar (5) or the like, the at least one cord (8 , 9) being spring-loaded at its respective other end, c h a r a c t e r i z e d in that said winding device is according to one of claims 1 to 5.

7. A screening device according to claim 6 or 7 , c h a r a c t e r i z e d in that movement of the screening body (2 ) from said first to said second end position is obtained by a cord guidance comprising two cords (8 , 9) , each in one end being connected to a winding device (Ia, Ib) at one of said frame or sash members , and in the other end being connected to a bottom bar (5) or the like , the cords (8 , 9) being spring-loaded at their respective other ends .

8. A . screening ^'device ^• according to • claim 6 - or 7 , c h a r a c t e r i z e d in ^' that ^' when said screening body (2 ) is in said second end position, the at least one cord (8 , 9) is wound in two and only- two layers on said winding reel (Ic , Id) .