Patent Publication Number: US-2022213726-A1

Title: Piece of furniture with a door held by a displacement device

Description:
The invention relates to a piece of furniture, such as a wardrobe, with a one-part or multi-part door, in particular a foldable sliding door, which is held by a displacement device displaceable into a door compartment. 
     For closing an opening of a piece of furniture, doors are often used, especially foldable sliding doors, which when the piece of furniture has been opened can be slid into a door compartment. When the piece of furniture is opened, the door is turned to the side or folded. To ensure that the opened door does not appear disturbingly, it is then moved into the door compartment of the piece of furniture, which is usually separated from the interior of the piece of furniture by a partition wall. 
     U.S. Pat. No. 8,336,972B2 discloses a piece of furniture with a displacement device by means of which a foldable sliding door connected by hinges to a mounting profile can be pulled out of a door compartment, rotated in front of an opening and retracted back into the door compartment. The displacement device comprises a scissor cross which has two scissor elements which are pivotally connected to one another and which hold the mounting profile aligned in a vertical position during displacement within the door compartment. The scissor cross is connected to the mounting profile by a fastening device. After loosening the fastening device, the mounting profile can be moved vertically in relation to the scissor cross in order to position the door within the door compartment at an equal distance from the top and bottom of the piece of furniture. 
     If no scissors cross is used, it should be noted that parts of the lever mechanism may take up an undefined position before being connected to the mounting profile, so that the optimum position must first be determined with appropriate effort before connecting to the mounting profile. 
     The mounting profile is not only held by the scissor cross, but is also guided along an upper and a lower rail to avoid twisting and jamming of the scissor cross. 
     It should also be noted that a displacement device of this type can take up a relatively large amount of space, so that the door held by the displacement device cannot be sunk as far as desired into the door compartment of the piece of furniture. Accordingly, the door or foldable sliding door and its elements need therefore be dimensioned smaller. Alternatively, the door compartment is to be designed accordingly larger, so that the design of the displacement device may have an undesirable influence on the dimensions of the piece of furniture. 
     EP3029248A1 discloses a displacement device with a lever mechanism, which is designed as a scissor cross or parallelogram and has parallel levers, by means of which a mounting profile, which is hinged to a door, is slidably held. 
     US2014150208A1 discloses a piece of furniture that comprises a foldable sliding door with several door elements and a guide rail that extends along the front of the piece of furniture and into the door compartment through a 90° curve. In this piece of furniture, the front door element is held by a guide drive that runs ahead of the door when it is opened and closed. After the foldable sliding door has been retracted into the door compartment, the folding sliding door is therefore suspended on one side, which may cause the foldable sliding door to misalign. When the folding sliding door is retracted into the door compartment, the folded sliding door may therefore contact the top panel or bottom panel of the piece of furniture. Due to manufacturing and mounting tolerances the task of the displacement device of keeping the door or foldable sliding door in vertical alignment in any position within the door compartment may therefore not always be optimally fulfilled. 
     The present invention is therefore based on the object of creating an improved piece of furniture with an improved displacement device. 
     With the improved displacement device the one-part or multi-part door shall be advantageously displaceable into a door compartment without contacting the floor or ceiling of the door compartment. 
     In particular, an improved displacement device shall be created for a piece of furniture that comprises a foldable sliding door with door elements, one of which is held by means of a guide carriage that is slidable along a guide rail that runs along the front of the piece of furniture and into the door compartment. 
     The displacement device shall occupy little space and allow the mounting profile to be moved over a maximum distance. 
     The displacement device shall keep the mounting profile with the associated door stable in vertical orientation over the entire displacement range and especially in the end positions. Further, any misalignment that occurs should be correctable in a simple manner and by simple means. 
     The displacement device shall further allow the mounting profile as well as the door to be mounted in a simple manner. 
     This problem is solved with a piece of furniture that comprises the features of claim  1 . Advantageous embodiments of the invention are defined in further claims. 
     The piece of furniture comprises a one-part or multi-part door, which serves to close an opening of the piece of furniture and which is connected by hinges to a mounting profile which is held within a door compartment by a displacement device displaceably between a first end position and a second end position, 
     which displacement device has a lever mechanism comprising four lever units rotatable in a plane, a first connection bridge and a second connection bridge and a centre bridge, 
     which centre bridge is pivotally connected on a first side by a first lever unit and a second lever unit, which are spaced apart and aligned parallel to one another, each to the first connection bridge, which is connected to at least one holding device mounted on the piece of furniture, and 
     which centre bridge is pivotally connected on a second side by a third lever unit and a fourth lever unit, which are spaced apart and aligned parallel to one another, each to the second connection bridge, which is connected to the mounting profile. 
     According to the invention in the first end position of the mounting profile the lever units are aligned at least approximately parallel to the first and second connection bridge and are at least partially sunk into the centre bridge, which centre bridge in this first end position of the mounting profile is at least partially sunk into one of the first and second connection bridges. 
     The first connection bridge can be connected to the holding device in one piece or detachably, if necessary via an adaptor. The second connection bridge can be connected to the mounting profile in one piece or detachably, if necessary via an adaptor. 
     Due to the parallel alignment of the parts of the displacement device in the end position, in which the door is fully inserted into the door compartment, and due to the mutual displacement of the parts of the displacement device into one another, only little space is required as a result. The centre bridge and the lever units and preferably also the connection bridges connected thereto can be moved completely or partially into one another, so that they are aligned in parallel with a minimum distance and are almost aligned coaxially. The door can therefore be driven into the door compartment over a maximum distance, therefore allowing the use of doors with a greater width. 
     The inventive displacement device is particularly advantageous for use in a piece of furniture comprising a foldable sliding door or a door with several door elements, of which one door element is held by a guide carriage which is slidable along a guide rail that comprises a first rail part extending along the front side of the piece of furniture and a second rail part extending inside the door compartment, which first and second rail part are connected to each other by a rail curve. 
     By means of the inventive displacement device, the door or foldable sliding door can be held vertically aligned in any position within the door compartment. 
     A misalignment of the door inserted into the door compartment can be easily compensated by a bearing element or corrected by adjusting the lever mechanism. 
     The displacement device can be changed between a first end position, in which the lever mechanism is fully folded and the door is fully inserted into the door compartment, and a second end position, in which the lever mechanism is fully unfolded and the door is moved out of the door compartment. 
     In preferred embodiments, the first and second lever units are connected by lever joints to the first connection bridge and to the centre bridge. In this embodiment, the third and fourth lever units are each connected by lever joints on the one hand to the second connection bridge and on the other hand to the centre bridge. 
     For the adjustment of the displacement device or of the lever mechanism, the distance between the lever joints and thus the distance between the axes of rotation of the lever joints of at least one of the lever units is preferably adjustable. Thereby an adjustment range is provided which allows for correcting maximum possible misalignments. 
     Preferably the distance of the lever joints and thus the distance of the corresponding rotation axes of the third and the fourth lever unit is adjustable, which form the underside of the lever mechanism and are particularly suitable for the correction of a possible inclination in the end position of the mounting profile with folded lever mechanism. 
     For changing the distance between two corresponding lever joints at least one of the lever joints is preferably displaceably mounted along the longitudinal axis of the associated lever unit and can be displaced and fixed by means of an adjustment device. 
     The adjustment device preferably comprises a bearing block mounted in the associated lever unit so as to be displaceable at least approximately along its longitudinal axis. The bearing block, which holds a joint shaft of the associated lever joint, is adjustable by means of an adjustment screw that is held rotatable and axially non-displaceable. The joint shaft determines the axis of rotation, so that the displacement of the bearing block also changes the distance of the axes of rotation of the respective lever unit. In this way the inclination of the held door or foldable sliding door can easily be adjusted, especially in the critical end position of the mounting profile with the lever mechanism folded. 
     The bearing block preferably has a cross section that is adapted to an internal cross section of the lever unit, which corresponds for example to a U-profile with retaining grooves or to a T-profile. The bearing block is thus held positively and can only be moved along the longitudinal axis of the lever unit. The adjustment screw is preferably aligned axially parallel or coaxial to the longitudinal axis of the lever unit and engages with the screw shaft in a threaded hole of the bearing block and can thus move it axially by turning the adjustment screw. To allow the joint shaft to be moved with the bearing block, appropriate longitudinal openings must be provided in the legs of the e.g. U-profile-shaped lever unit. The longitudinal openings preferably run parallel to the longitudinal axis of the lever unit and thus allow the displacement of the joint shaft and thus the axis of rotation of the lever joint. 
     The adjustment screw itself is held rotatable but axially not movable by a holding block. The holding block is, for example, clamped within the inner cross section of the lever unit or held in a slot, which, for example, extends perpendicular to the longitudinal axis of the lever unit and is provided therein. The holding block has for example ribs or wings on both sides, which can be inserted into holding grooves running perpendicular to the longitudinal axis of the lever unit. By inserting the adjustment screw and connecting it to the bearing block, which can only be moved axially, the holding block is thus also fixed in the receiving position. 
     The first and second lever units are rotatably held by the centre bridge and must therefore, before they can be connected to the mounting profile, be brought into a corresponding alignment, which is a mirror image of the alignment of the third and fourth lever unit. This connection is made in the second end position of the shifting device with an unfolded part of the lever unit which comprises the third and fourth lever unit which are already connected to the holding device or holding devices. The first and second lever units are not yet connected and are thus turned by gravitational force downwards against the floor of the door compartment. It is therefore an object to facilitate the precise connection of the lever mechanism to the mounting profile and especially to avoid multiple readjustments. 
     In order that the installer does not have to determine the alignment himself, a balancing device is preferably provided which ensures that the first and second lever units are always aligned symmetrically to the third and fourth lever unit. The balancing device comprises two balancing levers connected by a sliding joint to one another, the ends of which are each connected to an associated lever unit in such a way that they form a four-bar linkage. The two balancing levers are connected with lever units of the lever mechanism lying at the same level, i.e. with the first and third lever unit and/or the second and fourth lever unit. The balancing unit can therefore be designed in one or two parts. The diagonally opposite lever joints of the resulting four-bar linkage form pairs of joints that behave in opposite ways. If one pair of joints approaches, the distance of the other pair of joints increases and vice versa. The sliding joint is slidably guided and held in a guide track of the centre bridge and moves back and forth when the four-bar linkage is changed. 
     In this way it is ensured that the first and second lever units of the lever mechanism are always kept at the same level. The first and second lever units intended for connection to the mounting profile and the first connection bridge are therefore held in the second end position of the lever mechanism in a position where they can be connected to the mounting profile. It is therefore not necessary to manually hold the first and second lever units and the first connection bridge in a suitable position and make corrections if required. 
     It should be noted that the invention thus comprises different solutions which can also be implemented independently of each other, but which complement each other ideally. The adjustability of the distances of the axis of rotation of the lever mechanism by at least one adjustment device can be provided independently of the use of a one-piece or two-piece balancing device. Conversely, the balancing device can be used independently of the adjustability of the distances of the axis of rotation of the lever mechanism. Overall, however, when implementing all solutions the installation effort is considerably reduced. Incorrect settings and undesired misalignment of the door or the foldable sliding door as well as correspondingly complex corrective measures are no longer necessary. 
     Preferably in the piece of furniture or connected to the displacement device, damping elements are used which act directly or indirectly on the door, gently gripping it and accompanying it into the end position. 
     In preferred embodiments, the third and fourth lever units, which face the at least one holding device connected to the piece of furniture, each comprise two preferably plate-shaped lever elements, which are arranged at a distance from and preferably parallel to each other. Preferably also the first and second lever units facing the mounting profile each comprise two preferably plate-shaped lever elements, which are arranged spaced apart from each other and preferably parallel to each other. The lever units, however, are preferably designed as one piece. 
     The centre bridge preferably has an L-profile, an H-profile or a U-profile with a profile space limited by profile parts into which the associated first and/or second and/or third and/or fourth lever unit can be sunk. 
     Preferably, the third and fourth lever unit facing the at least one holding device connected to the piece of furniture or the first and second lever unit facing the mounting profile can be turned or shifted into the centre bridge. 
     In another preferred design, the first and second lever unit or the third and fourth lever unit are rotatably mounted on the outside of the centre bridge. 
     The lever units can therefore be aligned in parallel either inside or outside the centre bridge so that only a minimum of space is required. The lever units can be partially or preferably completely sunk into the centre bridge. 
     In a further preferred embodiment, the first or the second bar-shaped connection bridge will each have an L-profile or a U-profile, which has a profile space limited by profile parts or a neighbouring profile space into which parts of the lever mechanism can be inserted or turned. The profile spaces of the connection bridges can be identically or differently dimensioned. The connection bridges can preferably accommodate corresponding parts of the lever unit and of the centre bridge. If the profile spaces are differently dimensioned, it can be provided that one of the connection bridges not only takes up the lever units and the centre bridge, but also the other connection bridge completely or partially. 
     The lever units rotate downwards or upwards together when the lever mechanism is operated. The direction of movement is chosen taking into account whether the weight of the lever mechanism should support the insertion or extraction of the door. 
    
    
     
       Below, the invention is explained with reference to the drawings. Thereby shows: 
         FIG. 1  a piece of furniture  10  with a door  11  held by a mounting profile  85  prior to mounting an inventive displacement device  1 ; 
         FIG. 2  a piece of furniture  10  with an inventive displacement device  1 , which has a lever mechanism  5  with four lever units  51 ,  52 ,  53 ,  54 , which is connected on the one hand to holding devices  84 A,  84 B and on the other hand to a mounting profile  85 , on which a door  11  with two door elements  111 ,  112  is mounted by hinges  3 ; 
         FIG. 3  the piece of furniture  10  of  FIG. 2  with extracted door elements  111 ,  112 , of which the first door element  111  is hinged on one side to the mounting profile  85  and on the other side to the second door element  112 , which is held at the front by means of a guide carriage  6  displaceable along a guide rail  83 ; 
         FIG. 4  the displacement device  1  of  FIG. 2  and  FIG. 3  with the inversely mounted lever mechanism  5  with the first and second lever units  51 ,  52  connected to the holding devices  84 A,  84 B and with the third and fourth lever units  53 ,  54  connected to the mounting profile  85 ; 
         FIG. 5 a    the third and fourth lever units  53  and  54  of the lever mechanism  5  of  FIG. 2 , connected to the second connecting bridge  58 B and axially aligned thereto; 
         FIG. 5 b    the first and second lever units  51 ,  52  of the lever mechanism  5  of  FIG. 2 , axially aligned and connected to the first connecting bridge  58 A and to the centre bridge  55 ; 
         FIG. 5 c    the first and second lever units  51 ,  52  axially aligned and connected to the first connecting bridge  58 A and the centre bridge  55 , with the lever mechanism  5  partially open; 
         FIG. 5 d    a detailed view of the upper part of the centre bridge  552  and the lever elements  511 ,  512  of  FIG. 5 c   , which are connected to each other by the upper centre lever joint  563 ; 
         FIG. 5 e    a detailed view of the lower part of the first connecting bridge  58 A and the lever elements  521 ,  522  of  FIG. 5 c    connected by the lever joint  564  to a profile blade  581 ; 
         FIG. 5 f    the completely folded displacement device  1  of  FIG. 2 ; 
         FIG. 6 a    the upper end of the displacement device  1  of  FIG. 5   f;    
         FIG. 6 b    a detailed view of the displacement device  1  of  FIG. 6   a;    
         FIG. 7 a    the lever mechanism  5  of  FIG. 4  in a preferred embodiment; 
         FIG. 7 b    the lever mechanism  5  of  FIG. 7 a    supplemented with two balancing devices  7 ; 
         FIG. 8 a    the lower part of the lever mechanism  5  of  FIG. 7 a    with second and fourth lever units  52  and  54 , each equipped with an adjustment device  59 ; 
         FIG. 8 b    in enlarged view the second lever unit  52  of  FIG. 8 a    with the adjustment device  59 ; 
         FIG. 9 a    a part of one of the lever units  51 ,  52 ,  53 ,  54  with an inserted adjustment device  59 , which comprises a displaceable and adjustable bearing block  591 , by which a joint shaft  595  of an associated lever joint is held; 
         FIG. 9 b    the adjustment device  59  of  FIG. 9 a    in a longitudinal section; 
         FIG. 9 c    the multi-part joint shaft  595  of  FIG. 9   a;    
         FIG. 10 a    a displacement device  1  with the folded lever mechanism of  FIG. 7 a   ; and 
         FIG. 10 b    the displacement device  1  of  FIG. 10 a    without the connection bridges  58 A,  58 B. 
     
    
    
       FIG. 1  shows a piece of furniture  10  with a door  11  held by a mounting profile  85  prior to the installation of a displacement device  1 . About half of the door  11  has been driven into a door compartment  14 , which is delimited by an outer wall  12  and a partition wall (removed) of the piece of furniture  10 . The mounting profile  85  is pivotally connected to the door  11  with three hinges  3 , so that the door  11  can be pulled out of the door compartment  14  and rotated to cover an opening of the piece of furniture  10 . 
     The mounting profile  85  is guided within the door compartment  14  along a displacement axis y by means of support carriages  88  (symbolically shown) attached to an upper and a lower holding rail  81 ,  82 . The holding rails  81 ,  82  absorb the weight of the door  11 . However, tilting moments t of the door  11 , which cause it to tilt, cannot be compensated by the holding rails  81 ,  82  and running gear. The mounting profile  85  is therefore connected in a further mounting step to a displacement device  1  as shown in  FIG. 2  or in  FIG. 7 a   . By means of the displacement device  1 , the mounting profile  85  and thus the door  11  is always precisely held in vertical alignment over the entire displacement range. Any misalignments can be easily corrected. The displacement device  1  can also be mounted easily and precisely by using a balancing device  7  (see  FIG. 7 b   ). 
       FIG. 2  shows parts of the piece of furniture of  FIG. 1  with a two-part door or foldable sliding door  11  with a first door element  111 , which is guided with the mounting profile  85  along the holding rails  81 ,  82  and connected by hinges  30  to a second door element  112 . The second door element  112 , which is retracted into the door compartment  114  at the front, is connected at the front to a guide carriage  6  (symbolically shown), which is guided in a guide rail  83 . The guide rail  83  has a first rail section  831  extending parallel to the front of the piece of furniture  10  and a second rail section  832  extending into the door compartment  14 . The two rail sections  831 ,  832  are connected by a curved section  833 . The guide carriage  6  can therefore run over the entire area of the guide rail  83 . After extending and unfolding the foldable sliding door  11 , the drive  6  moves with the front side of the second door element  112  in front. 
     The piece of furniture  10  is now equipped with a displacement device  1 , which includes a lever mechanism  5 . 
     In  FIG. 2  the foldable sliding door  11  is almost completely retracted into the door compartment  14  and is only held on one side by the displacement device  1  and by the drives guided along tracks  81 ,  82  and the guide rail  83 . The door  11  therefore has a strong tendency to tilt forward. Hence, if the displacement device  1  is not adjusted optimally, a misalignment of the door  11  results. 
     In a preferred embodiment, for the compensation of this inclination, a bearing element  9  is provided in the area of the front end of the door compartment  14 , on which the first and/or the second door element  111 ,  112  can be supported when present. Preferably the door elements  111 ,  112  are released from the bearing element  9  before they are turned in front of the opening of the piece of furniture  10 . A bearing element can be a bearing roller  9  for example, which is held by a bearing axle  99 . Preferably, several bearing elements are provided so that the load is divided. It is also possible to combine different bearing elements, e.g. the combination of a roller bearing and a plain bearing. 
     In a preferred embodiment, however, the misalignment is corrected by an adjustment or setting of the lever mechanism  5 , as described below. 
     The lever mechanism  5  comprises first and second lever units  51 ,  52 , which on one side are hinged together by a rod-shaped centre bridge  55  and on the other side by a first connection bridge  58 A, as well as third and fourth lever units  53 ,  54 , which are hinged together on one side by the centre bridge  55  and on the other side by a second connection bridge  58 B. 
     At the connection points of the resulting joint polygon, lever joints  561 ,  562 ,  563 ,  564 ,  565 ,  566  are provided which allow the mutual rotation of the connected elements. At the centre bridge  55  the two lever joints  565 ,  566  are provided, which are each connected with two lever units  51 ,  53  or  52 ,  54 . Alternatively, a lever joint  565 ,  566  can be provided on the centre bridge  55  for each of the lever units  51 ,  53  or  52 ,  54 . 
     The first connection bridge  58 A is connected in one piece or detachably to holding devices  84 A,  84 B, which are firmly mounted on the back, e.g. on the back wall or a sidewall of the piece of furniture  10 . The second connection bridge  58 B is connected in one piece or detachably to the mounting profile  85 , which is connected via hinges  3  to the foldable sliding door  11 . 
     The lever mechanism  5  shown in  FIG. 4  forms two mirror-symmetrical parallelograms which perform the same movements during the retraction and extraction of door  11 . The lever units  51 ,  53 ,  52 ,  54  each have a first end piece E 11 ; E 31 ; E 31 ; E 41  and a second end piece E 12 ; E 32 ; E 32 ; E 42 . 
     When inserting the door  11 , the parts of the lever mechanism  5 , especially the lower and upper lever units  53 ,  54 ;  52 ,  54 , are inserted into one another and aligned parallel to one another. In some preferred designs, the lever units  53 ,  54 ;  52 ,  54  and the connection bridges  58 A,  58 B are inserted into one another. In a preferred embodiment, the parts of the lever mechanism  5  can also be shifted parallel to each other into the mounting profile  85 , thus minimizing the space requirement. 
       FIG. 3  shows the piece of furniture  10  of  FIG. 2  with extracted but not yet unfolded door elements  111 ,  112 , of which the first door element  111  is hinged on one side to the mounting profile  85  and on the other side to the second door element  112 , which is slidable along the guide rail  83  by means of the guide carriage  6 . The door  11  was gripped by a handle  112  and pulled out of the door compartment  114 . During this procedure the lever units  51 ,  52 ,  53 ,  54  and the centre bridge  55  were lifted. Additional force was therefore required to pull out the door elements  111 ,  112 . The insertion of the door elements  111 ,  112  is now supported by the weight of the lever elements  51 ,  52 ,  53 ,  54  and the centre bridge  55 . If, however, the extension of the door elements  111 ,  112  is to be supported by the weight of the lever elements  51 ,  52 ,  53 ,  54  and of the centre bridge  55 , the lever mechanism  5  is inverted as shown in  FIG. 4 . 
       FIG. 4  shows the displacement device  1  of  FIG. 2  and  FIG. 3  with inverted orientation of the lever mechanism  5  in a larger view, showing the design of the parts of the lever mechanism. 
     It is shown that the lever units  51 ,  53 ;  52 ,  54  each have two plate-shaped lever elements  511 ,  512 ;  531 ,  532 ;  521 ,  522 ;  541 ,  542 , which are held at an allocated distance from each other by the first and second peripheral upper lever joints  561 ,  563 ; the first and second peripheral lower lever joints  562 ,  564  and the upper and lower centre lever joint  565 ,  566 . 
     The U-profiled centre bridge  55  has two legs that are open in the direction of the holding devices  84 A,  84 B and in the direction of the first connecting bridge  58 A. The first connecting bridge  58 A, on the other hand, has a profile blade  581 , which is directed towards the centre bridge  55  and can enter between the legs of the centre bridge  55 . The profile blade  581  preferably has recesses into which joint shafts can enter. 
     The second connection bridge  58 B, which is connected to the centre bridge  55  by the third and fourth lever units  53 ,  54 , has a U-profile that is open towards the centre bridge  55  and can accommodate the entire folded lever mechanism  5 . 
     The distance between the plate-shaped lever elements  511 ,  512 ;  521 ,  522  of the first and second lever units  51 ,  52  connecting the centre bridge  55  and the first connection bridge  58 A is less than the distance between the side plates of the U-profile of the centre bridge  55  but greater than the width of the profile blade  581 . The plate-shaped lever elements  511 ,  512 ;  521 ,  522  held inside the U-profile of the centre bridge  55  can therefore be shifted into the U-profile of the centre bridge  55  and at the same time also hold the profile blade  581  of the first connection bridge  58 A as shown in  FIG. 5   b.    
     The distance between the plate-shaped lever elements  531 ,  532 ;  541 ,  542  of the third and fourth lever units  53 ,  54  facing the mounting profile  85  is greater than the width of the U-profile of the centre bridge  55 , so that the lever elements  531 ,  532 ;  541 ,  542  mounted on the outside of the centre bridge  55  can accommodate the centre bridge  55  in between. 
     At the same time the distance between the plate-shaped lever elements  531 ,  532 ;  541 ,  542  of the third and fourth lever units  53 ,  54  is smaller than the width of the second connection bridge  58 B, so that they can be turned downwards or upwards into the U-shaped second connection bridge  58 B, as shown in  FIG. 5 a   . With the plate-shaped lever elements  531 ,  532 ;  541 ,  542  of the third and fourth lever units  53 ,  54 , the lever pack of  FIG. 5 b    held in between can be turned into the U-shaped second connection bridge  58 B. During this procedure the first connection bridge  58 A is also inserted into the second connection bridge  58 B. 
       FIG. 5 a    shows the third and fourth lever units  53  and  54  of the lever mechanism  5  of  FIG. 4 , which are connected to the U-shaped second connection bridge  58 B and axially aligned with it. 
       FIG. 5 b    shows the axially aligned first and second lever units  51 ,  52  of the lever mechanism  5  of  FIG. 4  connected to the first connection bridge  58 A and the centre bridge  55 . 
       FIG. 5 c    shows the first and second lever units  51 ,  52  connected on one side to the first connection bridge  58 A and on the other side to the centre bridge  55  and axially aligned thereto with the lever mechanism  5  partially open. 
       FIG. 5 d    shows a detailed view of the upper part of the centre bridge  552  and the lever elements  511 ,  512  of  FIG. 5 c   , which are connected by the upper centre lever joint  563 ; 
       FIG. 5 e    shows a detail of the lower part of the first connection bridge  58 A and the lever units  521 ,  522  of  FIG. 5 c    connected to the profile blade  581  through the first peripheral lower lever joint  564 . 
       FIG. 5 f    shows the fully folded displacement device  1  of  FIG. 4 . 
       FIG. 6 a    shows the upper end of the fully folded displacement device  1  of  FIG. 5 f   . It can be seen that practically the entire lever mechanism is accommodated by the mounting profile  85  and therefore practically no additional space is required for the lever mechanism  5 . 
       FIG. 6 b    shows a detailed view of the displacement device  1  of  FIG. 6 a   . It is shown that in the second connection bridge  58 B held by the mounting profile  85 , the lever elements  531 ,  532  of the lever unit  53  and between them the centre bridge  55  are inserted, in which the lever elements  511 ,  512  of the lever unit  51  and between them the profile blade  581  of the first connection bridge  58 A are inserted. 
       FIG. 7 a    shows the lever mechanism  5  of  FIG. 4  in a preferred embodiment with U-shaped connection bridges  58 A,  58 B and an H-shaped centre bridge  55  as well as with one-piece lever units  51 ,  52 ,  53 ,  54 , each of which preferably having a U-shaped cross-section suitable for accommodating an adjustment device  59 . Adjustment devices  59  can be provided at all end pieces of all lever units  51 ,  52 ,  53 ,  54 . The lever mechanism  5  can be adjusted particularly advantageously if an adjustment device  59  is provided at the end piece E 21 , E 41  of the second lever unit  52  and/or the fourth lever unit  54  connected to the corresponding connection bridge  58 A,  58 B. By operating the adjustment device  59 , the lever axes of the corresponding lever unit  52  or  54  can be shifted against each other. The adjustment devices  59  are preferably adjusted in the folded state of the lever mechanism  5  to correct misalignment of the door or foldable sliding door  11 . The folded lever mechanism  5  with a view to the adjustment screws  59  is shown in  FIG. 10   a.    
       FIG. 7 a    also shows that the first and second lever unit  51 ,  52  can be inserted from one side and the third and fourth lever unit  53 ,  54  from the other side into the H-profile of the centre bridge  55 . In this procedure the first and second lever units  51 ,  52  and part of the centre bridge  55  are inserted into the first connection bridge  58 A and the third and fourth lever units  53 ,  54  and part of the centre bridge  55  are inserted into the second connection bridge  58 B. The joint shafts of the lever joints  561 ,  563 , which connect the first lever unit  51  with the first connection bridge  58 A and the third lever unit  53  with the second connection bridge  58 B, are inserted into receiving openings  550  provided in the centre bridge  55 . 
     The folded displacement device  1  with the folded lever mechanism  5  of  FIG. 7 a    is almost completely accommodated by the mounting profile  85  and takes up very little space. 
       FIG. 7 b    shows the lever mechanism  5  of  FIG. 7 a    supplemented with two balancing devices  7 . Since all parts of the lever mechanism  5  are coupled together, it would be sufficient to provide only one balancing device  7  for example to connect the second and fourth lever unit  52 ,  54 . If, on the other hand, the balancing devices  7  are to take up larger loads, two of them may be used. 
     Each balancing device  7  forms a 3-point pivotal connection with the lever mechanism  5 . Two points are connected to corresponding or mirror-symmetrical lever units  51 ,  53  or  52 ,  54 . The third point can be moved along the centre bridge  55 . 
     Each balancing device  7  comprises two balancing levers  71 ,  72 , which are connected to one another by a sliding joint  73  and which are connected each to the corresponding lever unit  51 ,  53  or  52 ,  54  by joints  711 ,  721 . The joints may be soft like the lever joints of the lever mechanism and typically comprise a joint shaft which pierces the corresponding levers or their end pieces. The sliding joint  73  is mounted in a guide track  551  of the centre bridge  55 . The corresponding lever units  51 ,  53  and  52 ,  54  are therefore always held by the balancing device  7  in a mirror-symmetrical position, i.e. with the same inclination to the centre bridge  55 . The second connection bridge  58 B can therefore easily be connected to the mounting profile  85  of  FIG. 1 . Corrections are either unnecessary or reduced to a minimum. The sliding joint  75 , for example, comprises a wheel with a circular wheel groove, which is limited by wheel flanges. The wheel is pierced centrally by a joint shaft which holds the facing ends of the balancing lever  71 ,  72 . 
     The balancing device  7  comprises two balancing levers  71 ,  72  which are connected to each other, on one side, rotatably by a sliding joint  73  and, on the other side, by joints  711 ,  721 , either to the first and third lever units  51 ,  53  or to the second and fourth lever units  52  or  54 . The joints may be of the same design as the lever joints of the lever mechanism and typically comprise a cardan shaft which passes through the corresponding levers or their end pieces. The sliding joint  73  is slidably mounted in a guide track  551  of the centre bar  55 . The corresponding lever units  51 ,  53  or  52 ,  54  are therefore always kept mirror-symmetrical by the balancing device  7 , i.e. with the same inclination to the centre bridge  55 . The second connecting bridge  58 B can therefore easily be connected with the mounting profile  85  of  FIG. 1 . Corrections are not necessary or are reduced to a minimum. The sliding joint  75  includes, for example, a wheel with a circular wheel groove, which is limited by wheel flanges. The wheel is passed centrally through by a joint shaft which holds the facing ends of the balancing levers  71 ,  72 . 
       FIG. 7 b    shows that guide track  551  has an inlet opening  5510 , into which the sliding joint  73  is inserted in such a way that the edges of the guide track  551  adjacent to the inlet opening  5510  can engage in the wheel groove as guide flanges. The sliding joint  73  is thus held in guide track  551  and can only be moved axially along this guide track  551  or axially along the longitudinal axis x of the centre bridge  55  (see  FIG. 7 a   ). When turning the corresponding lever units  51 ,  53  or  52 ,  54 , the balancing levers  71 ,  72  turn around the resulting balancing axes or joint axes s 1 , s 2 , s 3  of the joints  711 ,  721 ,  731 . 
     Already with the installation of one balancing device  7 , all parts of the lever mechanism  5  are positively guided, which is why the first and second lever units  51 ,  52  are guided mirror-symmetrically to the third and fourth lever unit  53 ,  54 , even if they are not yet guided by the holding rails  81 ,  82 . The precise positioning of the lever mechanism  5  for connection with the mounting profile  85  of  FIG. 1  will therefore take place automatically. 
       FIG. 8 a    shows the lower part of the lever mechanism  5  of  FIG. 7 a    with the second and fourth lever units  52  and  54 , each equipped with an adjustment device  59 . It can be seen that the first and second connection bridge  58 A,  58 B each have a U-profile, which are open towards each other. The centre bridge  55  has an H-profile into which the second and fourth lever units  52 ,  54  can enter. The centre bridge  55  can enter the U-profile of the facing connection bridge  84 A or  84 B on both sides. Please note that there is space between the legs of the U-profiles of the connection bridges  84 A,  84 B and the lever units  52 ,  54  in which the side plates of the H-profile of the centre bridge  55  can enter. 
       FIG. 8 b    shows an enlarged view of the second lever unit  52  of  FIG. 8 a    with the adjustment device  59  provided at its end piece E 21 . The end piece E 21  of the second lever unit  52  passes partially through an opening  585  in the first connection bridge  58 A, so that the adjustment device  59  is easily accessible for adjustment purposes. 
     The adjustment device  59  comprises a bearing block  591  which is mounted in the lever unit  52  so as to be displaceable along its longitudinal axis. The bearing block  591 , which holds a joint shaft  595  of the associated lever joint  562 , can be adjusted by means of an adjustment screw  593  which is held rotatable and axially not displaceable. By turning the adjustment screw  593  the bearing block  591  can therefore be moved along the longitudinal axis h of the lever unit  52 . The joint shaft  595  determines the position of the axis of rotation. Hence, by moving the bearing block  591  also the distance of the axes of rotation of the respective lever unit  562  changes accordingly. In this way, the inclination of the held door or folding-sliding door  11  can easily be adjusted, especially in the critical end position of the assembly profile  85  with the lever mechanism  5  folded. 
       FIG. 9 a    shows a part of one of the lever units  51 ,  52 ,  53 ,  54  with an inserted adjustment device  59 , which comprises the displaceable and adjustable bearing block  591 , by which the joint shaft  595  of the corresponding lever joint  562  is held. 
       FIG. 9 b    shows the adjustment device  59  of  FIG. 9 a    in a longitudinal section. The reference numbers  51 ,  52 ,  53 ,  54  indicate that the adjustment device  59  can be mounted on each end of each lever unit  51 ,  52 ,  53 ,  54 . Preferably only one or two adjustment devices  59  are mounted. However, any number of adjustment devices  59  can be mounted. In principle, the joint shafts of the lever joints can also be shifted and adjusted against each other in other ways. For example, the lever unit  52  can be constructed in two parts and have overlapping elements which can be moved against each other and fixed in any position. Furthermore, the lever unit  52  can have two parts which are provided with threaded elements and connected to each other by a threaded rod. By turning the threaded rod the distance between the lever axes can also be changed. However, the use of the present compact and easily accessible adjustment device  59  is particularly advantageous. 
     The bearing block  591  of the adjustment device  59  has a cross section adapted to the internal cross section of the lever unit  52 , which has a U-profile with legs and leg feet directed towards each other. The bearing block  591  is thus held positively and can only be moved along the longitudinal axis h of the lever unit  52 . The adjustment screw  593  is coaxially aligned with the longitudinal axis of the lever unit  52  and engages with the screw shaft in a screw channel  5911  of the bearing block  591  and can move it axially by turning the adjustment screw  593 . In order that the joint shaft  595 , which is held in a bearing channel  5910  of the bearing block  591 , can now be moved with the bearing block  591 , corresponding longitudinal openings  95  are provided in the legs of the U-shaped lever unit  52 . The longitudinal openings  590  run parallel to the longitudinal axis h of the lever unit  52  and thus allow the displacement of the joint shaft  595  and thus of the axis of rotation of the lever joint  562 . 
     The adjustment screw  593  is held rotatable but axially not movable by a holding block  592 . The holding block  592  is clamped within the inner cross section of the lever unit  52  by means of a grub screw  594 . 
       FIG. 9 c    shows the multi-part joint shaft  595  of  FIG. 9 a   , which has a joint shaft screw  5951  and a joint shaft nut  5952 , which when screwed together form the joint shaft  595 , on which a swivel bushing  5953  is rotatably mounted. The bearing block  591  is held by the swivel bushing  5953  and can therefore rotate around the joint shaft  595  with virtually no friction. 
       FIG. 10 a    shows the displacement device  1  with the folded lever mechanism  5  of  FIG. 7 a    and  FIG. 10 b    shows the displacement device  1  of  FIG. 10 a    without the connection bridges  58 A,  58 B. The first connection bridge  58 A is connected to the holding devices  84 A,  84 B, which are mounted or mountable on the sidewall or rear wall of the piece of furniture  10  of  FIG. 1 . The second connection bridge  58 B is connected to the mounting profile  85  by an adaptor  589 . The mounting profile  85  can be moved along the adaptor  589  and can be fixed for example by a screw. 
     LIST OF REFERENCES 
     
         
           1  displacement device 
           10 ,  10 ′ piece of furniture, wardrobe 
           11  door, particularly foldable sliding door 
           111  first door element 
           112  second door element 
           113  handle 
           12  sidewall 
           13  partition wall 
           14  door compartment 
           3  hinges 
           5  lever mechanism 
           51  first lever unit 
           511 ,  512  lever elements of the first lever unit 
         E 11 , E 12  end pieces of the first lever unit 
           52  second lever unit 
           521 ,  522  lever elements of the second lever unit 
         E 21 , E 22  end pieces of the second lever unit 
           53  third lever unit 
           531 ,  532  lever elements of the third lever unit 
         E 31 , E 32  end pieces of the third lever unit 
           54  fourth lever unit 
           541 ,  542  lever elements of the fourth lever unit 
         E 41 , E 42  end pieces of the fourth lever unit 
           55  centre bridge 
           550  receiving openings for the lever joints  561 ,  563   
           551  guide track in the end piece  559   
           5510  inlet opening 
         E 51 , E 52  end pieces of the centre bridge 
           561 ,  562  first and second upper peripheral lever joint 
           563  upper centre lever joint 
           564 ,  565  first and second lower peripheral lever joint 
           566  lower centre lever joint 
           58 A first connection bridge 
           58 B second connection bridge 
           581  profile blade 
           585  window openings in the connection bridges  58 A/B 
           589  adaptor 
           59  adjustment device 
           590  bearing window 
           591  bearing block 
           5910  bearing channel 
           5911  screw channel 
           592  holding block 
           593  adjustment screw 
           594  locking screw 
           595  joint shaft 
           5951  joint shaft screw 
           5952  joint shaft nut 
           5953  swivel bushing 
           6  guide carriage 
           7  balancing device 
           71  first balancing lever 
           72  second balancing lever 
           75  sliding joint 
           81  lower holding rail 
           82  upper holding rail 
           83  guide rail 
           84  holding device 
           84 A first holding device 
           84 B second holding device 
           85  mounting profile 
           88  support carriages in the holding rails  81 ,  82   
           9  bearing element, bearing roller, plain bearing 
           99  bearing axle for the bearing element 
         s 1 ,s 2 ,s 3  balancing axes 
         z longitudinal axis of the centre bridge  55