Abstract:
A car door-shaft door coupling for arrangement on a door wing with a door leaf plane includes a pivoting lever, which is rotatably mounted on a rotational axis on a support element, and a moveable element, which is coupled to the pivoting lever in such a manner that a movement of the moveable element carried out parallel to the door leaf plane causes the pivoting lever to perform a rotational movement for coupling a car door to a shaft door and change the distance between the lever and the door leaf plane by horizontal movement.

Description:
FIELD 
       [0001]    The invention relates to a car door/shaft door coupling usable for coupling a car door with a shaft door in a door system of an elevator installation. 
       BACKGROUND 
       [0002]    Such car door/shaft door couplings are used in order to couple a car door leaf, which is actuated by a door drive, with a shaft door leaf. An elevator car comprises a door drive and a car door. The car door has at least one car door leaf and a car door threshold. In addition, individual shaft doors each with at least one respective shaft door leaf and shaft door threshold can be arranged along an elevator shaft in which the elevator car can be vertically moved. 
         [0003]    The shaft doors are usually closed. In the case of corresponding positioning at a predefined stopping position of the elevator car in the elevator shaft an interior space of the elevator car can be entered via one of the shaft doors and the car door. This requires synchronous opening or closing of the car door leaf and shaft door leaf at this stopping position, which can be ensured by the car door/shaft door coupling. The car door/shaft door coupling can be fixed to a car door leaf. 
         [0004]    A coupling device which can be actuated by the car door/shaft door coupling for the purpose of a coupling is accordingly arranged at the shaft door leaf at the predefined stopping position. In that case, an area at each shaft door in which the car door/shaft door coupling can engage in the coupling device is predefined and very limited. It is characterized by a spacing, which is projected along the travel path of the elevator car, of the elevator car door threshold from the shaft door threshold in the form of a gap. When dynamic tolerances occur such as, for example, car movements or static tolerances such as, for example, building displacements it can happen in the case of travel of the elevator car that the car door/shaft door coupling can collide with the shaft door threshold or the coupling device. 
         [0005]    EP 0 829 446 shows a pivotably mounted car door/shaft door coupling. The car door/shaft door coupling comprises two pivot levers and two entrainer cams. The entrainer cams are so mounted on the pivot levers parallelly to one another that when rotational movement of the pivot lever occurs they maintain their orientation and change their spacing from one another. The change of this spacing serves the purpose of coupling a car door leaf with a shaft door leaf. The rotational movement of the pivot lever is achieved by means of a coupling of the car door/shaft door coupling with a door drive. The pivot levers are rotatably mounted on a base plate, which can be pivoted out of the afore-mentioned gap by means of an additional actuator. This is achieved in that the car door/shaft door coupling is retracted from the gap during the elevator travel and correspondingly prevents, in the case of building displacements or car movements, the car door/shaft door coupling from being able to collide with the shaft door threshold or the coupling device. A disadvantage of such a car door/shaft door coupling is that it is of complicated construction. 
       SUMMARY 
       [0006]    It is therefore the object of the present invention to create a car door/shaft door coupling having a simplified construction. 
         [0007]    The object is fulfilled by a car door/shaft door coupling which is provided for arrangement at a door leaf, comprising a pivot lever, which is mounted on a support element to be rotatable at an axis of rotation, and a movable element, which is so coupled with the pivot lever that a movement of the movable element executed parallelly to a door leaf plane has the effect that the pivot lever executes a rotational movement for coupling of a car door with a shaft door and at the same time changes its spacing from the door leaf plane by means of a horizontal movement. The object is also fulfilled by a door system of an elevator installation with a car door/shaft door coupling of that kind. 
         [0008]    The invention is based on the recognition that the gap, which is characterized by a spacing—which is projected along the travel path of the elevator car—of the car door threshold from the shaft door threshold can be very tightly dimensioned due to regulations. In addition, the width of the gap during operation of the elevator car does not remain stable. This effect can be amplified by an elevator shaft which is higher and by an elevator car moved more rapidly in this elevator shaft. A car door/shaft door coupling, which is currently provided for that purpose and the coupling components of which can be retracted from this gap during elevator travel, has a complicated construction and is unnecessarily expensive due to actuation by two different drive means. 
         [0009]    In order to minimize these outlays it was sought to utilize the movement of an single drive means not only for the movement of the components of the car door/shaft door coupling in the gap, but also for the coupling movement thereof. This is achieved in that the movement of a single drive means causes on the one hand, by the connection thereof with the pivot lever, a rotational movement of the pivot lever and on the other hand at the same time a longitudinal movement of the pivot lever along its axis of rotation. The movement of the sole drive means thus ensures that the car door/shaft door coupling is brought into position in the gap and that the coupling movement of the pivot lever belonging to the car door/shaft door coupling takes place. There is thus also the possibility of separating the operation of the car door/shaft door coupling from a door drive used for displacing the door leaf. The simultaneous execution of the longitudinal movement and rotational movement of the pivot lever enables fastest possible coupling of a car door with a shaft door. 
         [0010]    In a development of the car door/shaft door coupling the car door/shaft door coupling has a first slide surface and a second slide surface, which are so inclined relative to the door leaf plane that in the case of movement of the movable element executed parallelly to the door leaf plane the first slide surface executes on the second slide surface a sliding movement which produces the rotational movement and the horizontal movement of the pivot lever. The movement of the movable element can be transferred in this way to the pivot lever. 
         [0011]    In a development of the car door/shaft door coupling the first slide surface is constructed to be complementary with second slide surface. The guidance of the sliding movement can be improved in that way and the car door/shaft door coupling executed to be more stable. 
         [0012]    In a development of the car door/shaft door coupling an entrainer element and preferably a second entrainer element parallel to and at a spacing from the entrainer element are mounted on the pivot lever, wherein the at least one entrainer element is mounted on the pivot lever at a respective entrainer axis parallel to and spaced from the axis of the rotation. The rotational movement of the pivot lever in that way leads to a possible spreading of the entrainer elements, in which case at the same time the orientation of the entrainer elements can be maintained. In that way, different geometries of an entrainer parallelogram can be realized and the device can be adapted in situ to specifics of the doors. 
         [0013]    In a development of the car door/shaft door coupling a second pivot lever, at which the entrainer element is rotatably mounted in such a way that the entrainer element maintains its orientation at all times, is rotatably mounted on the support element. 
         [0014]    In a development of the car door/shaft door coupling the movable element is coupled with the pivot lever at a mounting axis parallel and spaced from the axis of rotation. A possibility is thus given of converting the longitudinal movement of the element into a rotational movement of the pivot lever. 
         [0015]    In a first variant of embodiment of the car door/shaft door coupling the car door/shaft door coupling can comprise a guide device at which the support element is guided perpendicularly to the door leaf plane, wherein the guide device is provided for the purpose of being fastened to a door leaf. In this variant of embodiment is possible to form the slide surfaces at the support element on the one hand and at the movable element on the other hand to be increased in size and thus to reduce material wear. In addition, the pivot lever can have a slot and the movable lever a pin, wherein the pin engages in the slot. In that way the movable element can be connected with the rotatable pivot lever in different forms of embodiment so that the movement can be transmitted. 
         [0016]    In a second variant of embodiment of the car door/shaft door coupling the support element can be provided so as to be part of a door leaf or to be fastened to the door leaf. The door leaf can include parts of the car door/shaft door coupling, in which case material can be saved. It is also possible to reinforce the door leaf in the region of the car door/shaft door coupling. The support element can in that case have the first slide surface and the pivot lever can have the second slide surface in the form of threaded surfaces. The pivot lever can be connected with the movable element by means of a bearing. In that way the movement of the movable element can be transmitted to the rotatable pivot lever. 
         [0017]    In a development of the door system of the elevator installation the door system comprises a secondary car door/shaft door coupling and an actuator, wherein the actuator executes an actuator movement which causes the movement of the element of the car door/shaft door coupling and a secondary movement, which is substantially equal to the movement, of a secondary element of the secondary car door/shaft door coupling. The two car door/shaft door couplings can thus be operated synchronously. The actuator can comprise a drive motor. It is advantageous that the device for coupling the car door with the shaft door can be operated by means of a single drive motor. 
         [0018]    In a development of the door system of the elevator installation the door system comprises a door leaf, wherein the door leaf comprises a pendulating guide mount with at least two damping elements and a floating block mounted in the pendulating guide mount and coupled with the support element of the car door/shaft door coupling, wherein the floating block is spring loaded against abutments in horizontal direction parallel to the door leaf plane at both sides by a respective one of the damping elements and wherein at least one pendulating guide limiter of the pendulating guide mount prevents pendulating movement in directions not corresponding with the horizontal direction parallel to the door leaf plane. Thus, centering of the car door/shaft door coupling between coupling elements arranged at the door to be coupled can be achieved during the coupling process so that larger tolerances in the orientation of the car door/shaft door coupling with respect to the coupling elements facing it are possible. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0019]    The invention is explained in more detail in the following by way of figures, in which: 
           [0020]      FIG. 1  shows an elevator installation with a car door/shaft door coupling according to the prior art; 
           [0021]      FIG. 2  shows a first variant of embodiment of the car door/shaft door coupling according to the invention in a perspective view; 
           [0022]      FIG. 3  shows a door system with the car door/shaft door coupling according to  FIG. 2  in a side view; 
           [0023]      FIG. 4  shows a second variant of embodiment of the car door/shaft door coupling according to the invention; 
           [0024]      FIG. 5  shows a bearing for coupling an element with a pivot lever of the car door/shaft door coupling in a sectional illustration; 
           [0025]      FIG. 6  shows a door system with two car door/shaft door couplings; 
           [0026]      FIG. 7  shows a first variant of embodiment of a centering device for a door system; 
           [0027]      FIG. 8  shows a second variant of embodiment of a centering device for a door system; and 
           [0028]      FIG. 9  shows a third variant of embodiment of the car door/shaft door coupling according to the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0029]      FIG. 1  shows an elevator installation  1 . The elevator installation  1  comprises an elevator shaft  2  and an elevator car  6  movable in the elevator shaft  2 . The elevator installation  1  comprises a door system  52 . A shaft door  3  and a car door  7  of the elevator car  6  are part of this door system  52 . The door system  52  comprises a car door/shaft door coupling  53  according to the prior art. The car door  7  has a car door threshold  13  and a car door leaf  9 . The shaft door  3  has a shaft door threshold  4  and a shaft door leaf  15 . The car door leaf  9  forms, parallel to the surface of its door leaf, a door leaf plane  26 . The shaft door leaf  15  is arranged to be parallel to the car door leaf  9 . 
         [0030]    A spacing of the shaft door threshold  4  from the car door threshold  13  characterizes a gap having a width prescribed, inter alia, by legal regulations. The door system  52  comprises two coupling elements  17 ,  17 ′, which in  FIG. 1  are arranged one behind the other and located at the shaft door side. The car door/shaft door coupling  53  is arranged at the car door side and comprises two entrainer elements  30 ,  30 ′. The coupling elements  17 ,  17 ′ are arranged within the gap  8 . If the entrainer elements  30 ,  30 ′ during travel of the elevator car  6  are disposed within the gap  8  it is possible for the entrainer elements  30 ,  30 ′, for example, to contact the shaft door threshold  4  or the coupling elements  17 ,  17 ′. 
         [0031]    Forms of embodiment of a car door/shaft door coupling  11 , which can be part of a door system  12  for coupling a car door with a shaft door in an elevator installation, are shown in  FIGS. 2 to 4  and  9 . The door system  12  can be positioned in place of the door system  52  of  FIG. 1 , wherein coupling elements can be arranged similarly to  FIG. 1 . Parts of the car door/shaft door coupling  11  can be retracted at least partly out of a gap as indicated, for example, in  FIG. 1 . The car door/shaft door coupling  11  comprises a pivot lever  14 , a movable element  18  and a support element  40 . The pivot lever  14  is mounted on the support element  40  to be rotatable at an axis  16  of rotation. The support element  40  can be provided for the purpose of being part of a door leaf or being fastened to a door leaf. The movable element  18  is coupled with the pivot lever  14  at a bearing axis  20 . An entrainer element  30  can be borne on the pivot lever  14  at an entrainer axis  28 . The entrainer axis  28  is parallel to the rotational axis  16  of the support element  40  and can be spaced therefrom. A second entrainer element  30 ′ can preferably be borne on the pivot lever  14  at a second entrainer axis  28 ′, which is similarly parallel to the axis  16  of rotation. The axis  16  of rotation is preferably oriented perpendicularly to a door leaf plane  26 , which can also be projected onto the support element  40  of the car door/shaft door coupling  11 . 
         [0032]    The movable element  18 , driven by an actuator (not illustrated) which can be part of the door system  12 , can execute a movement S oriented parallelly to the door leaf plane  26 . In that case it does not matter whether the movement S is executed to be parallel to the door leaf plane  26  or whether only a directional component of this movement S is oriented parallelly to the door leaf plane  26 . The movement S can also be executed to be perpendicular within a door system of an elevator installation. The coupling of the movable element  18  with the pivot lever  14  has the effect that the pivot lever  14  mounted at the support element  40  executes a rotational movement D. 
         [0033]    The car door/shaft door coupling  11  ( FIGS. 2 to 4 ) has a first slide surface  22  and a second slide surface  24 , which are inclined relative to the door leaf plane  26  and can be arranged to complementary. By complementary arrangement of the slide surfaces  22 ,  24  it is meant that the slide surfaces  22 ,  24  can slide against one another or slide along one another. At the same time, the movement S has the effect that the first slide surface  22 , which can face the movable element  18 , slides on or along the second slide surface  24 , which can face the support element  40 , by means of a sliding movement G. Due to the inclination of the slide surfaces  22 ,  24  the pivot lever  14  therefore equally executes a horizontal movement H, which is performed perpendicularly to the door leaf plane  26 . A spacing of the pivot lever  14  from the door leaf plane  26  is changed in correspondence with this horizontal movement H, i.e. the pivot lever  14  projects, due to the sliding movement G, into the gap between car door threshold and shaft door threshold. This means that the horizontal movement H and the rotational movement D are executed simultaneously. 
         [0034]    The car door/shaft door coupling  11  shown in  FIG. 9  has, instead of the slide surfaces  22 ,  24  shown in  FIGS. 2 to 4 , a changed movement transmission mechanism which couples the movable element  18  with the support element  40  and thus produces a horizontal movement H of the support element  40 . The pivot lever  14  executes, just like the support element  40 , the horizontal movement H. 
         [0035]    With regard to the functionality of the car door/shaft door coupling  11  shown by way of example in  FIGS. 2 to 4  and  9  it does not matter whether the horizontal movement H is executed perpendicularly to the door plane  26  or horizontally or whether only a directional component of this horizontal movement H is oriented perpendicularly to the door plane  26  or horizontally as long as in that case the functionality of the car door/shaft door coupling  11  is given. In addition to the fact that the pivot lever  14  protrudes, due to the rotational movement D, into the gap its rotational movement D serves the purpose that the entrainer elements  30 ,  30 ′ coupled therewith are brought into a position in which they couple with the coupling elements of the coupling device. In a door system with such a car door/shaft door coupling  11  the rotational movement D thus produces a coupling of a car door with a shaft door. 
         [0036]    The car door/shaft door coupling  11  can comprise a second pivot lever  14 ′ on which the at least one entrainer element  30 ,  30 ′ is mounted. The second pivot lever  14 ′ is rotatably mounted on the support element  40  and, by virtue of the movements of the entrainer elements  30 ,  30 ′, executes a passive rotational movement D′. The rotational movement D′ of the second pivot lever  14 ′ corresponds with the rotational movement D of the pivot lever  14 . In that way, orientation of the at least one entrainer element  30 ,  30 ′ in the elevator installation during coupling and decoupling processes can be maintained. The car door/shaft door coupling  11  is preferably arranged at the car door side, but can also be arranged at the shaft door side. Consequently, coupling elements of the door system  12  are arranged on the complementary side. The described sequence of movements S, D, H of the car door/shaft door coupling  11  can also be employed on door systems with different variants of embodiment of a car door/shaft door coupling according to the invention. In order that the movement S of the movable element  18  can be converted into the rotational movement D and the horizontal movement H of the pivot lever  14  the car door/shaft door coupling can have, instead of the mentioned slide surfaces  22 ,  24  ( FIGS. 2 to 4 ) or the movement transmission lever  100  ( FIG. 9 ), alternative movement transmission mechanisms. 
         [0037]      FIGS. 2 and 3  show a first form of embodiment of the car door/shaft door coupling  11 . The car door/shaft door coupling  11  comprises a schematically indicated guide device  42  (not illustrated in  FIG. 2 ), on which the support element  40  is mounted. The guide device  42  makes the horizontal movement H of the support element  40  possible. The guide device  42  is provided for the purpose of being fixed to a door leaf. The guide device  42  can comprise, for example, a tension spring so that mutual contact of the two slide surfaces  22 ,  24  and thus the horizontal movement H of the support element  40  can be ensured at all times. However, the support element  40  and the pivot lever  14  do not execute a horizontally oriented movement relative to one another, i.e. the pivot lever  14  and the support element  40  are always at the same spacing. The first slide surface  22  is arranged at the movable element  18  and the second slide surface  24  at the support element  40 . The movable element  18  has a pin  34 . This pin  34  engages in a slot  32  of the pivot lever  14  in order to convert the movement S of the movable element  18  into a rotational movement D of the pivot lever  14 . For realization of such a pin able to execute a movement relative to the support element  40  the support element  40  can be provided with a slot  33 . Alternatively thereto the pin  34  can be coupled with the pivot lever  14 , in which case the pin  34  goes past the support element  40 . 
         [0038]    The car door/shaft door coupling  11  of  FIG. 3  is arranged at a car door leaf  9 . A boundary  55 , which is defined by a car door threshold, of a gap is illustrated and is explained in the description with respect to  FIG. 1 . Consequently, in accordance with this illustration the car door/shaft door coupling  11  does not project into this gap. A movement S of the movable element  18  with respect to the illustrated guide device  14  on the one hand produces a horizontal movement H of the support element  40  and thus of the at least one pivot lever  14 ,  14 ′ along its axis  16  of rotation away from the car door leaf  9 . The entrainer elements  30 ,  30 ′ are thus moved into this gap beyond the boundary  55 . On the other hand, such a movement S produces spreading of the entrainer elements  30 ,  30 ′ due to the rotational movement D, which results from this movement S and is caused by the pin  34 , of the pivot levers  14 ,  14 ′. A movement S of the movable element  18  in the opposite direction, thus away from the illustrated guide device  42 , causes the corresponding opposite. 
         [0039]      FIG. 4  shows a second form of embodiment of the car door/shaft door coupling  11 . The movable element  18  is connected with the pivot lever  14  by means of a bearing  35 . The first slide surface  22  is arranged at the pivot lever  14  and the slide surface  24  is arranged at the support element  40 . The slide surfaces  22 ,  24  have the form of threaded surfaces which can be complementary. 
         [0040]    The movement S, which according to  FIG. 4  is directed downwardly, of the element  18  on the one hand produces the horizontal movement H of the at least one pivot lever  14 ,  14 ′ along its axis  16  of rotation. In that case, the spacing of the at least one pivot lever  14 ,  14 ′ from the illustrated door leaf plane  26  increases. Thus, the entrainer elements  30 ,  30 ′ can be moved into the previously mentioned gap. On the other hand, such a movement S produces spreading of the entrainer elements  30 ,  30 ′ due to the rotational movement D, which results from this movement S, of the pivot levers  14 ,  14 ′. Accordingly, the car door leaf  9  can be coupled with a shaft door leaf. A movement S, which is directed upwardly in accordance with  FIG. 4 , of the element  18  produces the corresponding opposite. 
         [0041]      FIG. 9  shows a third form of embodiment of the car door/shaft door coupling  11 . The car door/shaft door coupling  11  illustrated in  FIG. 9  shows, by contrast to the car door/shaft door coupling  11  illustrated in  FIG. 3 , a changed movement transmission mechanism which couples the movable element  18  with the support element and thus produces the movement H of the support element  40 . Consequently, the slide surfaces  22 ,  24  illustrated in  FIG. 3  are replaced by a movement transmission lever  100 . The movement transmission lever  100  comprises two lever bearings  102 ,  104 . The movement transmission lever  100  is pivotably mounted on the movable element  18  at a first one of the lever bearings  102 . The movement transmission lever  100  is pivotably mounted on the support element  40  at a second one of the lever bearings  104 . The movement S of the movable element  18  has the effect, by means of a movement of the movement transmission lever  100 , that the support element  40  and thus also the pivot lever  14  execute a horizontal movement H oriented perpendicularly to the door leaf plane  26 . Instead of the sliding movement G illustrated in accordance with  FIG. 3 , the movement of the movement transmission lever  100  has the consequence that the support element  40 , thus also the pivot lever  14 , executes the horizontal movement H. 
         [0042]      FIG. 5  shows a sectional illustration of a bearing  35  according to  FIG. 4 . The bearing  35  can be part of a door system  12 . The bearing can comprise, for example, a part of a movable element  18 , which can execute a movement S, and a part of a pivot lever  14 . The pivot lever  14  itself is, according to  FIGS. 2 to 4 , rotatably mounted at an axis of rotation. The preferably vertically directed movement S has the effect that the part of the pivot lever  14  executes, due to its rotatable mounting, a movement of which the components are a vertically directed movement component SK and a horizontally directed movement component H. 
         [0043]      FIG. 6  shows a front view of an elevator car  6  with a door system  12 . The door system  12  comprises a car door/shaft door coupling  11 , a secondary car door/shaft door coupling  11 ′, door leaves  9 ,  9 ′ and an actuator  50 . The car door/shaft door coupling  11  is arranged at a door leaf  9  of the elevator car  6  and the secondary car door/shaft door coupling  11 ′ is arranged at a secondary door leaf  9 ′. The door leaves  9 ,  9 ′ are so coupled to a drive element  62  of a door drive  60  that during operation of the door drive  60  they execute a door movement TB for opening/closing a door opening. 
         [0044]    The actuator  50  comprises a drive motor  54  and a transmission linkage  56 . The car door/shaft door coupling  11  comprises a movable element  18  and the secondary car door/shaft door coupling  11 ′ comprises a secondary movable element  18 ′. The mode of functioning of the movable elements  18 ,  18 ′ is explained in  FIGS. 2 to 4 . Operation of the drive motor  54  causes an actuator movement B of the actuator  50 . 
         [0045]    The movable elements  18 ,  18 ′ of the car door/shaft door couplings  11 ,  11 ′ are so mounted on the transmission linkage  56  that the movable element  18  executes a movement S parallel to a door leaf plane  26  and the secondary element  18 ′ executes a secondary movement  8 ′. The secondary movement  8 ′ is in that case substantially the same as the movement S. The movement S corresponds with the movement S which was explained in the description of  FIGS. 2 to 4 . The actuator movement B accordingly produces a coupling of a car door with a shaft door. Consequently, the coupling of the car door with the shaft door can be executed by the actuator movement B independently of the door opening movement TB. 
         [0046]      FIGS. 7 and 8  show two variants of embodiment of a centering device  75 ,  76  as part of door panels  9 . Such a centering device  75 ,  76  can, together with a car door I shaft door coupling according to the invention, be a component of a door system of an elevator installation. The centering device  75 ,  76  comprises a pendulating guide mount  84  and a floating block  80 . The pendulating guide mount  84  comprises at least two damping elements  88 ,  90  and at least one pendulating guide limiter  94 ,  96 . The pendulating guide mount  84  can be fixed to, for example, the door leaf of a door panel and therefore has a door leaf plane  26 . The part of the car door/shaft door coupling  11  fastenable to the door panel  9  can be attached to the floating block  80 . For example, this part can be the support element  40  of the variant of embodiment, which is described in  FIG. 4 , or the guide device  42  of the variant of embodiment, which is described in  FIGS. 2 and 3 , of the car door/shaft door coupling  11  according to the invention. The floating block  80  is mounted in the pendulating guide mount  84 . A movement of the floating block  80  along pendulating guide limiters  94 ,  96 , is limited by abutments  91  of the pendulating guide mount  84 . In that case, the centering device  75 ,  76  can be so fixed to the door leaf of an elevator installation that the movement of the floating block  80  along the pendulating guide limiter runs in horizontal direction. 
         [0047]    The pendulating guide mount  84 , which is illustrated in  FIG. 7 , of the centering device  75  comprises four pins  94  as pendulating guide limiters, which preferably extend parallel to the door leaf plane  26 . The floating block  80  has guide bores corresponding with the pins  94 . In this way the floating block can be moved along the pins  94  parallel to the door leaf plane  26 . Four damping elements are arranged in the form of springs  88 , which surround the pins  84  longitudinally between the abutments  91  and the floating block  80 . These springs  88  enable spring-loading of the floating block  80  between the abutments  91  and thus self-centering of the car door/shaft door coupling, which is fastenable to the floating block  80 , during the coupling process between the coupling elements of a door system. 
         [0048]    By contrast to the centering device  75  illustrated in  FIG. 7 , the pendulating guide mount  84 , which is illustrated in  FIG. 8 , of the centering device  76  comprises two resilient blocks  90  as damping elements and a linear guide  96 , preferably a dovetail guide, as pendulating guide limiter. The floating block  80  is provided with a groove corresponding with the linear guide  96 . By means of the linear guide  96 , which preferably extends parallelly to the door leaf plane  26 , the floating block  80  can be moved in the pendulating guide mount  84  between the abutments  91  parallelly to the door leaf plane  26 . Arranged on either side of the floating block  80  and between the abutments  91  and the floating block  80  is a respective one of the resilient blocks  90 . These resilient blocks  90  enable spring-loading of the floating block  80  between the abutments  91  and thus self-centering of the car door/shaft door coupling, which is fastenable to the floating block  80 , between the coupling elements of a door system. 
         [0049]    In accordance with the provisions of the patent statutes, the present invention has been described in what is considered to represent its preferred embodiment. However, it should be noted that the invention can be practiced otherwise than as specifically illustrated and described without departing from its spirit or scope.