DE3731123A1 - Device for guiding sliding-door elements aligned with one another in a closed position, especially for cupboards or the like - Google Patents

Abstract

Device for guiding sliding-door elements aligned with one another in the closed state, above all for cupboards and other similar pieces of furniture, with a guide pair for each sliding-door element. These guides are at the bottom and top, inside the respective piece of furniture, on the front edge of the door aperture. In these guide pairs (1a-2a/1b-2b), the respective wing (P1-P2) can slide unimpeded, by means of corresponding yokes (3a-3b/4a-4b/5a-5b/6a-6b), on the guides which are themselves provided with corresponding sliding elements. The guide pairs (1a-1b/2a-2b) consist of a first rectilinear front guide (11a-11b) and of a second rear guide (12a-12b) which has a rectilinear portion (121a-121b), extending parallel to the front guide, and a curved portion deviating from the front guide (11a-11b). This front guide (11a-11b) is equipped with guide parts (14a-14b/24a-24b) which extend at right angles from the guide and are directed towards the rear guide (12-12b). Corresponding sliding elements of the respective wing (P1-P2) can be moved in these guiding parts, since at least one of the guide parts is provided with removable sliding and fastening means which allow a positioning of the wing in the closed position. The guide system is provided to be used for at least one sliding-door element (P1-P2), with at least one... a ... Original abstract incomplete. <IMAGE>

Description

The present invention relates to a device for guiding sliding door elements that are in closed posi tion form a plane, i.e. aligned coplanar to one another and which are normally operated by hand, depending but also automatically with the help of a motor drive is possible. The device is particularly suitable for cabinets or similar pieces of furniture.

Various types of sliding doors and various are known its applications.

With a widespread type of sliding doors that are in under The doors are used in a wide variety of areas of pairs of sliding elements, each sliding element in two straight, parallel guide rails pairs, namely an upper and a lower pair, the same th.

In the furniture sector in particular, designs of this type are used of doors, especially for example with different Ab measurement, etc. provided. Especially with this type of application The sliding elements slide on adjacent parallel blocks Levels that are offset from one another, so that in closed Position the formed area is interrupted and thus the Aesthetic design is impaired, which is particularly the case Furniture disturbs.

There are also sliding doors with the structure described above knows, but their sliding elements in corresponding guides gen slide so that the elements in the open position to to allow access to the interior, to lie on top of each other and in the fully closed position, next to each other are aligned.

These doors that give a piece of furniture a better aesthetic Appearance require a complicated construction in order to a corresponding hold for the door elements and a to ensure appropriate leadership. You are therefore with a considerable expense both in terms of Manufacture of the doors as well as their assembly.

It would therefore be desirable and this is the task of the present Lowing invention to exclude the disadvantages described above sen, and a guide system made up of a reduced number of Sharing to create structures that are effortless and easy enables quick assembly of the doors themselves. The operation the door can be done by hand or automatically with the help a simple motor drive.

The aforementioned object is achieved with a device for guiding Sliding door elements with the features of claim 1 solved. Advantageous refinements and developments result ben from the subclaims.

According to the invention there is a guide for each sliding door element pair, i.e. a group of lower guides and a group provided by upper guides, these guides depending because at the bottom and at the top of the doorway inside the concerned Fenden piece of furniture are arranged in the front edge area. In the guide pairs, the respective wing element can unge prevents sliding by using these guides over cor corresponding bracket equipped with sliding elements is connected and said pairs of guides each consist of a first rectilinear front guide that runs the entire length of the Wing element itself runs, and a second rear Consist of a straight line parallel to the guide first front guide extending section and on her End has a curved portion opposite the first front guide deviates.

The said first front guide is also on her opposite end equipped with guide parts that run at right angles from the guide and referred to th rear guide are directed towards. In these tours can use the corresponding sliding parts of the respective element be moved, said guide parts with remove Available sliding and fastening means are provided that the Positioning of an element in the closed position possible lichen. The device sees the application of at least one nem pair of sliding door elements and thus the use of min at least one group of two pairs of guides, namely above and below, in front, these pairs of guides being symmetrical to one another and form a central part, the two parallel to one another includes other extending guide portions. The rear ab cuts run into two curved, deviating from the respective front guides cut out. At the end of at least one of the said Füh Stanchions are appropriate braking and / or spring-loaded stops funds provided. In addition, preferably automa table actuators are provided, which consist of egg nem corresponding electric gear motor exist, the engages in a rack, which in turn is attached to the respective gene element is attached.

For a more detailed explanation of the device for guiding Flü gel door elements and the advantages that can be achieved with them standing a preferred embodiment as an example and without Claim to be complete in a detailed manner under Be referring to the drawings:

Here show:

Fig. 1, 2, 3, views in longitudinal section of the guide system for a sliding door with two door elements in three positions. In each presentation, the upper guide group arranged on the top and in the lower part the lower guide group arranged at the bottom of the respective piece of furniture (not shown) is in the upper part. In the right part of Fig. 1, the side views of an individual guide elements are also shown;

Fig. 4, 5 in cross section an enlarged view of the lower guide Einzelan group and in a schematic way a possible embodiment of a motor drive;

Fig. 6, 7, 8 according to Fig 4 and 5, the ent-speaking part of the upper guide assembly with the fastening device in ge connected position of the door elements.

Fig. 9, 10 in the form of spring-loaded brake and stop elements for limiting the movement of a door element, which is provided on the group of the upper guides and for clarity collectively again gege only in certain positions in Figures 1, 2 and 3 are ben.

Fig. 11, 12, 13, 14 each in two elevations, the shape of the mounting bracket of the door elements and

Fig. 15 is a cross-sectional view according to the line II in Fig. 3.

In the figures, all common details are provided with the same reference symbols. From Figs. 1, 2 and 3 it can be seen that said guides each consist of two mutually symmetrical parts, namely a right and a left part, which are attached to the floor and to the ceiling of the respective piece of furniture and so the Füh approximately pairs form that allow sliding of the respective Türele Mentes of the sliding door.

As already mentioned, the lower guide is in each case in the un The lower part of the figures is shown, while the upper part tion is shown in the upper part. Both tours are different for functional reasons, since the below Ren guides corresponding small rollers with horizonta ler axle must carry, while the upper guides only the Take up and guide sliding rollers with a vertical axis ha ben.

As can be clearly seen from the figures, the lower guide consists of a first part 1 a and a second part 1 b with an exactly mirror-image shape and the upper guide consists of a first part 2 a and a second part 2 b , both also with a mirror image Education.

These parts 1 a , 1 b , 2 a , and 2 b consist of one piece that can be easily produced from a suitable material, for example a suitable plastic material, by means of drop forging or similar known techniques. For the sake of simplicity, only a lower and an upper guide part will be described below, reference being made to the part shown in the left-hand section of the cited figures.

The lower guide part 1 a consists of a front rail 11 a and a rear rail 12 a , each, as can be seen in the section on the right side of Fig. 1 and more clearly in Fig. 15, from a web of rectangular cross-section consists, wherein the web is arranged vertically and its upper Knate is rounded in order to be able to engage in grooves of castors with a horizontal axis of rotation, as described below.

The front clearly identifiable rail 11 a runs straight over its entire length, while the rear rail 12 a has a first also straight and parallel to the front rail 11 a at a corresponding distance from the same extending section 121 a , but as in the left Part of the figure shown, in a second ge curved, opposite the said front rail 11 a deviating portion 122 a merges.

The two rails 11 a and 12 a are held on a connection plate 13 a , which forms a suitable surface for fastening the supply of the entire guide element 1 a at the bottom of the Möbelstüc kes (see Fig. 15).

In the area directed towards the center, the two rails 11 a and 12 a are interrupted over a short section, with a substantially rectangular guide element 14 a being provided at right angles away from the rear rail. In the sem element, which is open at the top, slides a carriage 15 a , the shape of which can be seen more clearly from FIGS. 4, 5 and 15, and the functions of which will be described later ben.

The upper guide member 2 a shows, as seen from Figs. 1, 2 and 3 clearly ersichtbar also, a similar shape as the lower guide part. It differs from this in that instead of said rail 11 a and 12 a ent speaking rails 21 a and 22 a are arranged, which we sentlichen consist of C-profiles and form grooves, as shown in detail in the right part of Fig . 1 and also MACHINES SHOW cher in Fig. 15 can be seen.

In these profiles slide rollers held with a vertical axis of rotation slide, as described below. The be said upper guide part 2 a also shows a front re, completely straight rail 21 a and a rear rail 22 a , which has an initially straight, parallel to the front rail 21 a extending portion 221 a , but at its end in a second , deviating, curved section 222 a corresponding to said second deviating, curved section 122 a of the lower guide element 1 a passes. On the opposite side, a guide element 24 a is provided in accordance with the guide element 14 a of the lower guide part 1 a, which consists essentially of a grooved section of the same shape as the corresponding guide 21 a and from this at right angles in the direction of the adjacent rear guide 22 a runs, where in said guide element 24 a , as described below be, a corresponding roller 51 a can intervene.

In this case, too, the front rail 21 a and the rear rail 22 a are connected via a plate 23 a so that they form an integral part.

Said guide element 24 a is also equipped with a device which enables the respective sliding door element to be attached in the closed position.

The device is described in detail below with reference to FIGS . 6, 7 and 8, which show the arrangement in its three basic functional positions. As can also be seen from FIGS. 1, 2 and 3, who the upper and lower guide unit supplemented by further Füh approximately elements, which in terms of their shape, as already mentioned, exactly match the described Führelemen th 1 a and 2 a and in right part of said figures are shown.

These further guide elements and their individual parts are identified in the figures with the same reference numerals, but with the addition of the letter b .

One thus obtains lower guides, consisting of the elements 1 a and 1 b , and upper guides from elements 2 a and 2 b , these elements each in the front area of the lower edge F and upper edge S of the door opening of the cabinet (or a similar one Furniture), (not shown in Figs. 1, 2 and 3 is provided, but can be seen in the cross-sectional view of Figure 15) are attached.

In these guide groups, the door elements P 1 and P 2 , as clearly shown in FIGS. 1, 2, 3, and 15 Darge are finally used. Each of the elements P 1 and P 2 slides with means of four brackets in the guides, these brackets with ent speaking rotary elements, as shown in FIGS. 11, 12, 13 and 14 are equipped.

In Figs. 11 and 12, 11 of the lower middle clip 3 and in Fig. 12, the un tere side bracket 4, the two lower strap, shown in FIG., While Figs. 13 and 14, the two top bracket, FIG. 13 the upper middle Bü gel 5 and FIG. 14 shows the lower side bracket 6 .

It can be clearly seen that the middle and side brackets of the two elements P 1 and P 2 are of the same type, so that in this case too the respective parts in FIGS. 1, 2 and 3 with a code number followed by the usual Letters "a" and "b" are marked.

As can be seen from FIGS. 11 and 12, the brackets 3 and 4 are similar in that they actually consist of the practical angles 31 or 41 . They differ only by the fact that at the angle 31, a further, fixed Win angle 31 is fixed, the roller having a horizontal axis is arranged on the means of hinges, while at the angle 41 via the pin 45, which in the socket 46 engages, a white terer rotatable bracket 42 is attached vertically by means of a joint, which carries the roller 43 articulated with a horizontal axis. The two rollers 33 and 43 are, as clearly recognizable, provided with a circumferential groove in which the upper part of said rails engages, and arranged in two different planes, so that the first roller in the front rail 11 a and 11 b and the second roller in the rear rail 12 a and 12 b of the group of lower guides 1 a - 1 b can engage. In addition, the rollers 33 are provided in their front part with a cylindrical extension 331 , the function of which will be described below.

The top in FIGS. 13 and 14 shown bracket 5 and 6 are various types, in particular as regards Ver prolongation of their arms, wherein the side bracket 6 are longer than the central ironing and this for kinematic and radio tional reasons, as shown in Figures is clearly shown. 1, 2, and 3. Said, from the angles 51 and 61 Bü gel 5 and 6 are equipped at their free end and in the upper part with corresponding rollers 52 and 62 , the same design and are fastened vertically by means of joints.

As stated above, the lower guide elements 1 a and 1 b , which form the lower guide group, each include the Füh approximately element 14 a or 14 b , the structure and function of which will be described below with special reference to FIGS . 4 and 5 be. As can be seen from these figures, the carriage 15 a (or 15 b ) can move in the aforementioned guide element 14 a (or 14 b ) and so take two positions. A first position is shown in Fig. 4, wherein the carriage is fully engaged in accordance with the arrangement of Fig. 1, in which the respective sliding door element P 1 (or P 2 ) is in the closed position. A second position is shown in Fig. 5, wherein the genann te element is pulled out to occupy the position shown in Fig. 2 Po. The carriage 15 a (or 15 b ) is in its front upper section from two parts 151 and 152 provided, the connection of the respective rails 11 a (or 11 b ) and 12 a (or 12 in the second position of the carriage b ) manufacture.

Two springs 16 , which are hinged at their ends to two rungs 153 of the carriage 15 and to two outer rungs 142 of the side plates 141 on the sides of the guide element 14 a , hold the carriage 15 a (or 15 b ) in the two end positions fixed in a relocatable manner.

At the end of the rails 22 a and / or 22 b ge spring-loaded stop elements 7 and 8 are also provided, the structure of which is clearly shown in FIGS. 9 and 10 and whose function is described in detail below.

These resilient stop elements 7 and 8 are each fastened in the middle part of the group of upper guides and at the side ends thereof.

As can be seen from FIGS. 9 and 10, both types of the illustrated resilient elements consist of a suitable th, appropriately shaped steel wire that forms two round eyelets 71 and 81 at the free ends, two of which are joined together sections 72 and 82 go out, which in turn cut 73 and 83 at the opposite end in a Querverbindungsab. Each cross-connecting section is connected to the converging sections 72 and 82 via two curved side parts 74 and 84 , which allow a slight elastic deformation and thus a removal from the converging sections 72 and 82 when the cross-connecting section is pressed inwards. In the stop parts 7 , the two converging sections 72 are the same and symmetrical type, while the said sections are bent in the stop parts 8 to follow the curved th course of the ends 222 a or 222 b of the rails 2 a or 2 b .

The resilient stop parts 7 are fastened with the help of corresponding screws inserted into the respective round eyelets 71 , the screws engage in the openings 95 at the middle ends of the respective rails 22 a , while the resilient stop parts 8 in the same way in the openings 96 can be attached.

For the sake of simplicity, the two parts 7 are shown in Figs. 1 and 2 only on the upper guide element 2 a , while in Fig. 3 only a single part 8 is shown on the upper guide element 2 a .

As already mentioned in the description of the upper guide element 2 a , this is equipped with a further guide element 24 a , into which a device is used that holds the sliding door element P 1 in question in a resilient manner when the element is in the closed position.

The device which is described below, dargstellt schematically in FIGS. 6, 7 and 8. Reference is made to these figures below.

The guide element 24 a is open on one side, through the opening part of a movable member 25 having a substantially rectangular shape in the guide element 24 a penetrates the 251st This movable part 25 engages in a corresponding lateral guide opening. It is pressed into the interior of the guide element 24 with the aid of a spring 252. The part 251 is correspondingly shaped and has, on the front rail 21 a starting, a first section T 1 which is inclined inwards and a second, slightly outwardly inclined portion T 2 follows. The part 251 ends at the opposite end with a third curved section T 3 with a radius like that of the roller 31 a , which, as described below, must be blocked.

On the opposite side, a plate B is arranged in the wesent union square shape, the position with the open Po, as shown in Fig. 6, with one side on which a slot opening B 1 is provided, up to about half of the said guide element 24 formed opening engages.

The slot opening B 1 is located at a small distance from the adjoining side and thus forms a shaft B 11 .

The slot opening B 1 has the same width as the diameter of the roller 52 a , which engages in the opening.

The plate B is hinged in B 2 on the corresponding side of the Füh approximately element 24 and also provided with a rung B 3 , which slides in a corresponding to the Anlen effect in B 2 concentrically arranged slot B 4 , which determines the barrel. Between the rung B 3 and another stationary rung B 5 is arranged on the upper guide member 2 a spring B 6, which holds the plate tion B in their Endposi.

The function of the device described above will be next explained in its entirety.

First, the elements P 1 and P 2 of the sliding door, as shown in FIG. 1, are closed and aligned with each other. With the help of an appropriate handle (not shown) or in some other way, the middle part of the openable element is pulled out. This element is shown in FIG. 2 as element P 1 , for example. This movement causes a displacement of the carriage 15 a forward ne, which is thus moved from the position shown in FIG. 4 to the position of FIG . At the same time there is a displacement of the roller 52 a forward, the plate B rotated and the movable element 25 presses ge in its guide and so from the position shown in Fig. 8 in the end position of Fig. 6, in which it is completely pulled out is moved.

The element P 1 rotates around the side edge corresponding to the side opposite the pull-out and is positioned as shown in FIG.

As already mentioned, the on the lower bracket 4 a is articulated vertically to the subordinate role 43 a , so that it can rotate on the Bü gel and the prescribed rotation of the element P 1 allows.

By longitudinal displacement of the element P 1 in the direction of adjacent element P 2, the roll can 33 a and 52 a on the respective rails 11 a and 21 a slide roller. They follow a straight course, parallel to the element P 1 . At the same time, the roller 43 a and the roller 62 a first run through the respective different curved sections 122 a and 222 a of the rails 12 a and 22 a in question until they reach the subsequent straight sections 121 a and 221 a .

The element P 1 is then in a parallel and offset position in front of the adjacent element P 2. With a further offset, the element P 1 moves further in front of the element P 2 until it has reached the fully open position, as shown in FIG. 3 represents.

The door is closed in the opposite direction as described above.

The role 33 a (or 33 b ) is, as already mentioned, in its front part with a cylindrical extension 331 from.

This cylindrical part comes to rest when it runs in the displacement corresponding to the guide element 14 b (or vice versa 14 a , in the displacement of the element P 2 ) on the plate 17 b , which as shown in FIGS. 3 and 15, Lich, is arranged in front of said guide element 14 b.

The plate 17 b (or 17 a ) practically restores the continuity of the front rail 11 a ( 11 b ) when the Schlit th 15 a (or 15 b ) is positioned inside. As a result, the continuous support of the roller 33 a (or 33 b ) is guaranteed in this area for the displacement.

From the position shown in Fig. 3, the element P 1 , which is pushed laterally in the direction of the opening to be closed, initially leads on a straight line to the element P 2 adjacent to the end of the offset ge. The roller 43 a and the roller 62 a meet again on the different curved portions 122 a and 222 a , which ensure the subsequent feed of the corresponding page, so that the element P 1 again the position shown in Fig. 2 it reaches.

The opposite side is now pushed inwards (with part side in Fig. 1, 2, 3). As a result, the carriage 15 is displaced inward and takes the posi tion shown in FIG. At the same time, the roller 52 a , which is initially in the position shown in Fig. 6, is pressed inward and meets the first inclined portion T 1 of the movable element 25 , which is pressed into its guide opening and ge to the end of the Shank B 11 of the plate B acts, which begins to rotate about the pin D 2. The whole is shown in FIG .

The further penetrating roller 52 a slides on the second GE inclined portion T 2 of the movable element 25 , which now emerges and finally penetrates into the cavity formed by said curved portion T 3 , with a light te blocking takes place in this position.

Simultaneously, the said roller 52 penetrates a gradually into the slot opening B 1 and causes thereby a further rotation of the plate P, to the blocking position according to FIG. 8 is reached. The position of the said plate B is secured by the spring B 6.

The simultaneous action of the movable element 25 and the plate B ensures the necessary movable retention of the respective element in the closed position.

It can finally be seen that the movable element is initially braked shortly before reaching the outermost opening and closing posi tion and finally blocked in an elastic manner with the help of resilient stop elements 7 and 8 , as described above.

The function is as follows: when the roller 52 a / b or 62 a / b reaches the end area of the respective guide 22 a (or 22 b ), it first penetrates the deviating sections 72 or 82 of the corresponding spring-loaded stop element 7 or 8 a, whereby a slight braking effect is achieved. At the end of the path, it meets the connecting sections 73 or 83 , which causes a damped stop, since the sections 73 or 83 are elastically deformable.

As shown by way of example in FIGS. 1, 2 and 3, other stop elements can be provided which allow precise positioning of the elements. These elements are not described as they can be of different types in practice.

The system described can also be operated in an advantageous manner with the aid of a simple motor drive, as will be described below with reference to FIGS. 4 and be.

A summary is given in connection with these figures. As can be seen from the figures, the motor-operated device has a simple electrical gearbox M , which is arranged on a support N , which in turn is attached to the top S of the cabinet by means of a corresponding pin N 1 , which is a rotation of the whole its axis allows.

This unit is located on the side of the elements on which the handle is intended for manual operation. The gear M actuates a gear R which is arranged on a plane running parallel to the upper edge and thus at right angles to the element P 1 on which the motor gear acts, and on which a rack C is fastened. The axis of rotation of the gear R lies at a point on a vertical plane between the vertical through plane of the toothing of the rack C and the joint formed by the pin N 1 Ge.

The gear R engages in the said rack C only when actuated. For this reason, a corresponding, for example electromagnetic, coupling is provided which, for the sake of simplicity, is not shown in the figures.

This coupling also enables manual opening and closing of an element. The function of the device is extremely simple. If the gear motor M is set in rotation and the gear R rotates in the direction of the arrow, no longitudinal displacement of the element P 1 and thus the rack C is possible, and a moment arises through wel Ches the entire unit of the motor gear M to the front part, ie is rotated towards the element P 1.

As a result, a thrust effect is achieved, which gives rise to an offset at the output of the corresponding page. This offset corresponds fully to that as it is achieved in the manual actuation at the beginning of the opening process and which continues until the fully pulled out position shown in FIG. 5 is reached. Since now no further movement is possible, a longitudinal sliding of the rack C and thus the corresponding element P 1 is caused by the rotation of the toothed wheel R.

Corresponding control and regulation devices are just like corresponding stop elements, etc. known.

The invention has been illustrated by way of example in connection with a closet (or similar piece of furniture) with only two Sliding door elements explained. The device can be self-contained This also applies to cabinets with several sliding elements are provided. In this case you just need more lower and upper management groups, i.e., more precisely, one another group used for each additional sliding element will.

Claims (9)

1. Device for guiding sliding door elements that are aligned evenly to each other in the closed position, in particular for cabinets and similar pieces of furniture, characterized in,
that for each sliding door element ( P 1 , P 2 ) a pair of guides consisting of a lower guide ( 1 a , 1 b ) and an upper guide ( 21 , 2 b ) is provided,
that the guides are arranged below and above inside the door opening of the piece of furniture in the area of the front edge,
that the elements ( P 1 , P 2 ) have guide brackets ( 3 a , 3 b ; 4 a , 4 b ; 5 a , 5 b ; 6 a , 6 b ) with sliding elements,
that each guide has a first straight guide rail ( 11 a , 11 b ) extending over the total width of an element and a second rear guide rail ( 12 a , 12 b ) with a straight section (121 a , 121 b ) extending parallel to the front guide rail and a curved end portion ( 122 a , 122 b ) and
that the front guide rail (11 a , 11 b ) running at right angles to the guide rail to the rear guide rail directed guide parts ( 14 a , 14 b ; 24 a , 24 b ), in which the respective sliding elements of the corresponding sliding door element ( P 1 , P 2 ) are guided laterally displaceable. 2. Apparatus according to claim 1, characterized in that braking members ( 7 , 8 ) and / or resilient stop members are provided at the end of the guide rail. 3. Device according to one of claims 1 or 2 in Schie doors with two sliding elements, thus marked net that training and arrangement of the guide rails of the individual tours mirror images of one the contact area of the elements in the closed closed stood extending plane of symmetry are formed. 4. Device according to one of claims 1 to 3, characterized in that for actuating at least one of the wing door elements, a motor drive is provided which releasably engages in a rack attached to the element to be actuated ( C ). 5. Device according to one of claims 1 to 4, characterized in that the lower guide rails ( 1 a , 1 b ) are designed as guide webs ( 11 a , 12 a ; 11 b , 12 b ) which are on a common for attachment to the lower edge of the door opening suitable retaining plate are arranged. 6. Apparatus according to claim 5, characterized in that that to guide a wing door element with at least there are rollers provided with a guide groove, which are rotatably held perpendicular to the direction of movement are. 7. Device according to one of the preceding claims, there characterized in that the upper guide rails are designed as a T-profile, in which on the wing door elements preferably via connecting bracket gehal tene roles are performed. 8. Device according to one of the preceding claims, characterized in that each wing door element ( P 1 , P 2 ) in the region of its lower inner edge with two unte Ren brackets ( 3 a , 4 a ; 3 b , 4 b ) is provided on the inside and outside of the element itself are attached, the lower bracket ( 3 a , 4 a ; 3 b , 4 b ) with ent speaking rollers ( 33 a , 43 a ; 33 b , 43 b ) are equipped, which Hold element ( P 1 , P 2 ) while sliding on the web-like rails ( 11 a , 12 a ; 11 b , 12 b ). 9. Device according to one of the preceding claims, characterized in that each element ( P 1 , P 2 ) is equipped in the region of its upper inner edge with two upper brackets ( 5 a , 6 a ; 5 b , 6 b ), which on their side the inside and outside of the element are attached, these brackets ( 5 a , 6 a ; 5 b , 6 b ) are equipped with rollers ( 52 a , 62 a ; 53 b , 62 b ) which are vertically hinged to the brackets are and engage in the respective grooves of the rails ( 21 a , 22 a ; 21 b , 22 b ) of the upper guides ( 2 a , 2 b ).