DK1783318T3

DK1783318T3 - String tension tensioning cords on shade plants and shade plants

Info

Publication number: DK1783318T3
Application number: DK06123482.9T
Authority: DK
Inventors: Wilfried Gramsch; Guido Tants; JENS WüNSCHE
Original assignee: Hunter Douglas Ind Switzerland
Priority date: 2005-11-03
Filing date: 2006-11-03
Publication date: 2015-11-30
Also published as: PL1783318T3; EP1783318B1; EP1783318A3; DE102005052895A1; DE102005052895B4; SI1783318T1; EP1783318A2

Description

The invention relates to a cord tensioner for tensioning cords of shading units, especially pleated or (Roman) blinds, with a spring and a deflecting means attached to at least one end of the spring as well as another deflecting means for the cord. The invention further relates to a rail of a shading unit as well as a shading unit, especially pleated or (Roman) blinds with a moveable rail for a blind and cords for the blind, wherein at least one cord is tensioned by a spring. A cord tensioner of this type, a rail of this type and a shading device of this type are known from DE 90 04 641 U1.

Cord tensioners with a deflecting means attached to a spring are moreover known from GB 2 151 682 A and DE 90 05 275 U1.

Pleats, or also called pleated blinds, are shading units that are mainly mounted directly in front of a window pane in the window frames. They have at least one moveable rail that is manually moved for opening and pulling tight the blind. The opposite edge of the blind is fastened to a fixed rail that is fastened inside on the window frame. Recently, shading units with two moveable rails, where the blind is arranged between them, are becoming increasingly widespread. In this way any area can be shaded by the blind by adjusting the position of both moveable rails.

The moveable rails are displaceably arranged on cords. In practice, the cords are each fixed in the area of the corners of the window frame. In the area of the end of the moveable rail each cord is guided into the moveable rail, from there to the opposite end of the rail and then into the lower corner of the window underneath. With two moveable rails the cord is initially guided into the other moveable rail, namely again in the area of the second rail and from there to the opposite end of this rail. From there the cord is guided to the corresponding corner in the window frame. In practice, these cords are called the outer cords. By deflecting the outer cords onto the ends of the moveable rail and due to the resulting friction, the moveable rail and, with blinds having two moveable rails, both moveable rails are maintained in their respective position set by the user. For this purpose, and in order to keep the blind tight in a plane parallel to the plane of the window, the outer cords have to be tensioned to a certain degree. Flowever, other cords of the blind are also frequently tightened. Springs are used for this and are arranged at an appropriate place between the cords or at the ends of the cords in a fixed rail.The spring travel can also compensate for possible errors in the measurement of the window to be shaded, even though this is not its main function.

In the shading unit of EP 0 686 519 B1 a type of pulley is used as the cord tensioner, in which the loose blinds are spring loaded. The cord has to be mounted by threading it around the blinds. This type of installation is laborious. Additionally, recent attempts have been made to automate the assembly or at least to implement a machine-supported assembly process for the blinds, thereby requiring a particularly simple assembly.

With this in mind, the invention is based on the problem of creating a cord tensioner for tensioning cords as well as a shading unit having such a cord tensioner, such that the assembly is simplified and in particular can also be automated. Here it must be ensured that the cord does not release itself from the cord tensioner as this could lead to a malfunctioning blind.

In order to solve this problem the cord tensioner according to the invention and the shading unit according to the invention are characterised in that the deflecting means in a first position project over a housing in such a way that the cord with a bight can be wrapped around the deflecting means without difficulty and in a second position with the upper side of their covers fit flush with the housing, such that the cord is secured against slipping from the deflecting means.

In particular, the deflecting means has a first position (assembly position), in which the cord can be laid around the deflecting means, and another position (functional position), in which the cord is secured against slipping from the deflecting means.

Accordingly, the deflecting means for the cord can be brought into a first assembly position, in which the cord can be wrapped around the deflecting means in a simple manner. This can also be effected automatically. The deflecting means is then brought into its functional position. Here the cord is secured against slipping off and can no longer become lost. In a constructively simple way this securing can be carried out by guiding the cord in closed channels in the area of the deflecting means. It is therefore positively secured against slipping.

According to a constructive development of the invention, the one deflecting means is relocatable and the other deflecting means is fixedly arranged. In this regard the relocatable deflecting means should be pre-tensioned by the spring in a direction away from the fixed deflecting means. Due to the spring pretensioning the distance between the two deflecting means is thus increased. This is utilised to maintain the cord under tension. Possible measurement errors in the dimensions of the window to be shaded can also be compensated for.

For example the cord in a bight is wrapped around the deflecting means, i.e. once on the one deflecting means over to the other deflecting means, run around this back to the first deflecting means and around this again to the other deflecting means. Because of this enlacement in a bight the cord, as in a type of pulley, is doubly shortened in relation to the path of the moveable deflecting means. The spring itself can either be designed as a tension spring that pulls the moveable deflecting means away from the fixed deflecting means, or as a compression spring that is located between the moveable and the fixed deflecting means.

According to another development of the invention, both ends of the spring are each attached to a moveable deflecting means. In this way both outer cords can be tensioned by the spring with the added advantage that both cords are equally pre-stressed. According to a particularly preferred embodiment of the invention, a cord, in a bight however, is wrapped once around both deflecting means.

In the above described developments with two deflecting means, both deflecting means preferably have an assembly position and a functional position. The cord can thus be particularly easily assembled on both deflecting means and in particular can also be assembled automatically. The deflecting means or the deflecting means in their assembly position are only partially held in a bore hole, and after the cord is inserted by fully pressing in the deflecting means into the bore hole, they are brought into the functional position; this is particularly constructively simple.

In principle, the position of the cord tensioner inside a rail is completely irrelevant. Nevertheless, the cord tensioner should not slip to and fro in the rail. Therefore, according to a development of the invention, the cord tensioner is prevented from moving in the longitudinal direction of the rail. Constructively, this can be effected by means of a positioning catch on the cord tensioner which engages into a bore hole on the rail. Conversely, it is of course also possible to attach the positioning catch to the rail and the bore hole to the cord tensioner. However, the first variant has the advantage that usually a plurality of equally spaced bore holes are already arranged along the length of the rail, and which usually serve to guide cords for the pleated blind into the rail. They can be advantageously utilised in that the positioning catch engages into one of the bore hole.

As already indicated above, usually a pleated blind has not only the outer cords but also additional cords for tensioning the blind or the like. These are likewise partly guided inside the rail. In order that they can pass by the cord tensioner, a channel in the rail is provided beside the cord tensioner.

The invention is described below in more detail for an embodiment that is illustrated in the drawing. The figures show:

Fig. 1: a perspective view of a cord tensioner for tensioning cords prior to inserting the cord,

Fig. 2: a perspective view of the cord tensioner of Fig. 1 with an inserted cord,

Fig. 3: another perspective view of the cord tensioner of Fig. 1 with an inserted cord,

Fig. 4: a perspective view of a section of a rail with the inserted cord according to Figs 1 to 3,

Fig. 5: another perspective view of the rail of Fig. 4,

Fig. 6: the rail of Fig.4 in cross section.

In the Figures 1 to 3 there is shown a device for tensioning a cord 10, namely a cord tensioner 11. The cord tensioner 11 has a housing 12 that is produced in one piece as a plastic injection moulded part. The cord tensioner 11 has two deflecting means 13 and 14 for the cord 10. They are likewise produced in one piece from plastic and formed in an approximate T-shape, namely each with a cover plate 15 and 16.

The one deflecting means 14 is fixed to the housing 11 (fixed deflecting means 14), whereas the other deflecting means 13 is attached to a sliding carriage 17 (moveable deflecting means 13). The sliding carriage 17 is longitudinally relocatably mounted in a guide 18 in the housing 12, namely in a direction parallel to the longitudinal direction of the cord 10, and pre-tensioned by means of a tension spring 19 in a direction facing away from the other deflecting means 14.

The deflecting means 13 and 14 are inserted by means of a peg 20 and 21 respectively into bore holes 22, 23 in the sliding carriage 17 and in the housing 12 respectively. In the position illustrated in Fig. 1, the deflecting means 13 and 14 project far enough above the housing 12 such that the cord 10 with a bight 24 can be wrapped around the deflecting means 13, 14 without difficulty (assembly position). In the illustration of Fig. 1 the cord 10 coming from the left is guided to the fixed deflecting means 14 and guided around it back to the relocatable deflecting means 13, there again around this back towards the fixed deflecting means 14 and guided past it. This forms the bight 24. After the cord 10 has been wrapped around the deflecting means 13 and 14, the deflecting means 13 and 14 are pressed to their limit into the bore holes 22 and 33 respectively, such that the upper sides of the cover plates 15 and 16 are flush with the housing 12 (functional position). In this way, next to the deflecting means, a closed channel is formed, from which the cord can no longer slip out. The bight 24 of the cord 10 is secured against slipping out.

If a tensile force is exerted on the cord 10 then the relocatable deflecting means 13 is pulled against the force of the spring 19 towards the fixed deflecting means 14. In this way the cord 10 is held under tension. In this regard, the overall length of the cord 10 is adjusted, such that in a blind under normally occurring circumstances the relocatable deflecting means 13 is not pulled by the spring 19 against the end of the guide 18 facing away from the fixed deflecting means 14, i.e. not “in contact” against the arrestor. In a blind under normally occurring circumstances the tension in the cord 10 is thereby always maintained.

Smaller blinds require a lower tension of the cord 10 than do larger blinds. This tension can be adjusted by selecting a suitable spring 19 with an appropriate characteristic curve and by the spring pre-load.

The thus-described cord tensioner 11 is inserted into a rail 25 of a pleated blind. For this purpose the cord tensioner 11 has locking lugs 26 as well as locking bars 27. The cord tensioner 11 is pushed into the rail 25 with the locking lugs 26 and the locking bars 27 and positively locked behind protrusions 28 on the rail 25. As the cord tensioner 11, as can be seen in particular in Fig. 6, is narrower than the rail 25, this difference is formed by correspondingly designed long locking bars 27. This creates a channel 29 beside the cord tensioner 11, through which cords 30 that are not under tension can be guided past on the cord tensioner 11.

After the cord tensioner 11 has been clipped into the rail 25 in the above described manner, it can still be moved along the rail 25. This is harmless for the function of the cord tensioner 11, but is undesirable. Consequently, on the cord tensioner 11 there is a positioning catch 31 that in the present case has a slot 32, through which the one end of the cord 10 is fed through. On the rail 25 there are usually a plurality of bore holes 33 distributed along its length which usually enable cords to be guided into the rail 25. The cord tensioner 10 is clipped into the rail 25 in such a way that the positioning catch 31 engages into one of these bore holes 33. The cord tensioner 11 is positively secured from moving in the longitudinal direction of the rail 25.

List of reference numerals: 10 cord 11 cord tensioner 12 housing 13 deflecting means 14 deflecting means 15 cover plate 16 cover plate 17 sliding carriage 18 guide groove 19 spring 20 peg 21 peg 22 bore hole 23 bore hole 24 bight 25 rail 26 locking lug 27 locking bar 28 projection 29 channel 30 cord 31 positioning catch 32 slot 33 bore hole

Claims

A string tensioner for tightening a string (10) of a shading system, in particular the blinds or folding curtain, with a spring (19) and a redirection means (13) attached to at least one end of the spring (19) as well as a further redirection means (14) for the string (10), characterized in that the diverting means (13, 14) extend beyond a housing (12) in a first position, in such a way that the string (10) can be easily laid around the diverting means ( 13, 14) with a loop (24) and in a second position with the upper side of its covers (15, 16) flush with the housing (12) so that the cord (10) is secured against slipping of the redirecting means (13, 14). .

Conduit straps according to claim 1, characterized in that the conduit (10) is guided in closed channels in the region of the diverting means (13).

Drawstrings according to claim 1 or 2, characterized in that one of the diverting means (13) is arranged slidably and another of the diverting means (14) is arranged stationary.

Drawstrings according to claim 3, characterized in that the displaceable redirection means (13) are biased in a direction away from the stationary redirection means (14) by means of the spring (19).

Lanyard according to claim 1 or 2, characterized in that both diverting means (13, 14) are arranged slidably.

Drawstrings according to one of claims 3 to 5, characterized in that both diverting means (13, 14) have a mounting position and a functional position.

Drawstrings according to one of Claims 1 to 6, characterized in that the redirecting means (13) and (1) respectively. the diverting means (13,14) in their mounting position are only partially retained in a hole (22) and after insertion of the string (10) is brought into the functional position by fully pressing the redirecting means (13,14) into the hole (22).

Rail (25) of a shading system, especially the blinds or folding curtain, with a string tensioner (11) according to one of claims 1 to 7, wherein the string tensioner (11) is secured against longitudinal displacement of the rail (25), characterized in that the string tensioner (11) has a positioning nose (31) which engages a hole (33) on the rail (25).

Rail of a shading system, especially the blinds or folding curtain, with a string tensioner (11) according to one of claims 1 to 7, characterized in that a channel (29) is formed in the rail (25) next to the string tensioner (11). for additional cords (30).

Shading system, in particular blinds or folding curtains, with a movable rail (25) according to any one of claims 8 or 9 and cords (10), wherein at least one cord (10) is tightened by means of a spring (19) characterized by: that at least one end of the spring (19) is associated with a diverting means (13) for the cord (10).