Patent Publication Number: US-2022228417-A1

Title: Vehicle door device with a currentless opening function

Description:
CROSS REFERENCE AND PRIORITY CLAIM 
     This patent application is a U.S. National Phase of International Patent Application No. PCT/EP2020/063777 filed May 18, 2020, which claims priority to German Patent Application No. 10 2019 003 805.3, the disclosure of which being incorporated herein by reference in their entireties. 
    
    
     BACKGROUND 
     It is known to store potential energy in the form of potential energy or spring energy during the closing operation of the sliding door or pivoting/sliding door. After an emergency unlocking, this stored energy is then used in order to move the sliding door or pivoting/sliding door for a distance in the direction of the open position from the closed position. A further known possibility consists in providing a mechanical assembly which, during unlocking in the event of an emergency, not only overrides the existing locking of the sliding door or the pivoting/sliding door in the closed position, but also moves the sliding door or pivoting/sliding door by a certain distance in the direction of the open position by a mechanical connection. However, these solutions are all associated with a certain structural outlay. 
     SUMMARY 
     By contrast, disclosed embodiments provide a vehicle door assembly as discussed herein that, while having a simple design, permits opening of the sliding door or pivoting/sliding door by hand after an emergency unlocking. The intention is also to provide a vehicle with such a vehicle door assembly. 
     Disclosed embodiments relate to a vehicle door assembly and to a vehicle, for example, a rail vehicle with at least one such vehicle door assembly. 
     In accordance with various disclosed embodiments, a vehicle door assembly for a vehicle includes at least one sliding door which is slidable in a sliding direction in relation to a door frame having a door opening, or a pivoting/sliding door which is pivotable in a pivoting direction and is slidable in a sliding direction, by which the at least one sliding door or pivoting/sliding door is movable into a closed position closing the door opening and into an open position opening up the door opening and into any desired intermediate positions between the closed position and the open position, a door guide for guiding the at least one sliding door or pivoting/sliding door in relation to the door opening, a locking device for locking the at least one sliding door or pivoting/sliding door at least in the closed position, with an emergency unlocking device by which the at least one sliding door or pivoting/sliding door locked in the closed position can be unlocked in the event of an emergency. 
     Here, a vehicle should be interpreted to include any kind of vehicle, i.e., track-bound vehicles (rail vehicles) and also non-track-bound vehicles, vehicles with an engine and towed vehicles without an engine, such as trailers or towed carriages in rail vehicle combinations. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       Exemplary embodiments are illustrated below in the drawing and are explained in more detail in the description below. In the drawing 
         FIG. 1  shows a schematic side view of a vehicle door assembly according to a preferred embodiment with a sliding door in the closed position; 
         FIG. 2  shows a sectional illustration along the line II of  FIG. 1 ; 
         FIG. 3  shows a sectional illustration through a vehicle door assembly according to a further embodiment with the sliding door in the closed position; 
         FIG. 4  shows a perspective view of the vehicle door assembly from  FIG. 3  with the sliding door in an intermediate position, which is open for a distance, between the closed position and the open position; and 
         FIG. 5  shows a sectional illustration through a vehicle door assembly according to a further embodiment with the sliding door in the closed position. 
     
    
    
     DETAILED DESCRIPTION 
     As is known, a (pure) sliding door is mounted so as to be slidable only in one or along one sliding direction between the closed position and the open position, while, starting from the closed position, a pivoting/sliding door is first of all pivoted in a pivoting direction and then slid in a sliding direction until the open position is reached. Conversely, starting from the open position, a pivoting/sliding door is first of all slid along the sliding direction and then pivoted in a pivoting direction in order to adopt the closed position. A pivoting/sliding door therefore performs a combined pivoting and sliding movement. 
     Disclosed embodiments provide an, optionally, electrically actuated locking device, that locks and/or unlocks the at least one sliding door at least in the closed position, for example, may be unlocked electrically and locked by motor or mechanically by the door movement. The emergency unlocking device unlocks the at least one sliding door in the event of an emergency, optionally, without the action of electrical current, this being able to take place, for example, by mechanical elements which can be operated by hand. 
     Disclosed embodiments utilize a door guide for guiding the at least one sliding door or pivoting/sliding door along the sliding direction or along the pivoting direction is fastened, for example, to a body of the vehicle having the door opening. 
     Disclosed embodiments provide an emergency opening device for the at least partial emergency opening of the at least one sliding door or pivoting/sliding door in the emergency-unlocked state is provided which includes a currentlessly acting magnetic device, which comprises at least one first permanent magnet and at least one magnetically conductive element, and which, when the at least one sliding door or pivoting/sliding door is in the closed position and has been unlocked in the event of an emergency by the emergency unlocking device, exerts a magnetic force, which is generated without action of electrical current, on the at least one sliding door or pivoting/sliding door in such a manner that the at least one sliding door or pivoting/sliding door is pushed or pulled at least for a distance in the direction of the open position from the closed position, wherein the at least one first permanent magnet is statically connected to the at least one sliding door or pivoting/sliding door and the at least one magnetically conductive element is statically connected to the door frame or to the door guide, or wherein the at least one first permanent magnet is statically connected to the door frame or to the door guide and the at least one magnetically conductive element is statically connected to the at least one sliding door or pivoting/sliding door. 
     The term “magnetically conductive element” is intended to be understood as including, for example, an element which is at least partially composed of a ferromagnetic or paramagnetic material. As a result, no electrical current is necessary even for the emergency opening of the at least one sliding door or pivoting/sliding door. To the contrary, a magnetic force ensures an at least partial opening of the at least one sliding door or pivoting/sliding door. Since the at least one first permanent magnet and also the at least one magnetically conductive element are in each case arranged statically on the at least one sliding door or pivoting/sliding door or on the door frame or on the door guide, e.g., there is in each case a rigid connection between the at least one first permanent magnet and also between the at least one magnetically conductive element and the at least one sliding door or pivoting/sliding door or the door frame or the door guide, there are no kinematically interacting mechanical components by which the at least one first permanent magnet and/or the at least one magnetically conductive element are mounted somewhat movably (linearly, rotationally) on the door frame and/or on the door guide and/or on the at least one sliding door or pivoting/sliding door. This results in a structurally simple design of the emergency opening device. 
     In the case of a sliding door, the magnetic force ensures linear pulling or pushing of the sliding door out of the closed position along the sliding direction in the direction of the open position. In the case of a pivoting/sliding door, the magnetic force (initially) ensures pivoting of the sliding door out of the closed position along the pivoting direction in the direction of the open position because, in the case of pivoting/sliding doors, the first movement out of the closed position is always a pivoting movement. If necessary, the magnetic force can move the pivoting/sliding door beyond the initial pivoting movement into the following linear sliding movement along the sliding direction. 
     The magnetic force may be generated by the interaction between the at least one first permanent magnet and the at least one magnetically conductive element which, at least in the closed position, is located in the magnetic flux of the at least one first permanent magnet. 
     For example, the magnetic force is a magnetic reluctance force which acts between the at least one first permanent magnet and the at least one magnetically conductive element in such a manner that the magnetic resistance of the magnetic flux between the at least one first permanent magnet and the at least one magnetically conductive element is reduced when at least one door or sliding door is moved from the closed position in the direction of the open position. 
     In accordance with at least one embodiment, the magnetic force acts as a magnetic attraction force between the at least one first permanent magnet and the at least one magnetically conductive element, wherein the at least one first permanent magnet and the at least one magnetically conductive element, as seen in the closed position of the at least one sliding door or pivoting/sliding door and in the sliding direction of the at least one sliding door or in the pivoting direction of the at least one pivoting/sliding door, are arranged offset with respect to one another by an offset in such a manner that, in the emergency-unlocked state, the magnetic attraction force pulls the at least one sliding door or pivoting/sliding door at least for a distance, namely, for example, by the offset in the direction of the open position from the closed position. 
     Accordingly, it can be provided that:
         a) the at least one first permanent magnet is statically arranged on the at least one sliding door or pivoting/sliding door or is statically connected thereto, wherein, as seen in the sliding direction, a first portion of the door frame or of the door guide or of a first element fastened to the door frame or to the door guide has a higher magnetic conductivity than a second portion, or that   b) the at least one first permanent magnet is arranged on the door frame or on the door guide or is statically connected to the door frame or to the door guide, wherein, as seen in the sliding direction, a first portion of the at least one sliding door or pivoting/sliding door or of a second element fastened to the sliding door or pivoting/sliding door has a higher magnetic conductivity than a second portion,   c) wherein, in the closed position, the second portion at least partially overlaps with the at least one first permanent magnet, and the first portion, as seen in the sliding direction or pivoting direction, is arranged offset by the offset in the direction of the open position in such a manner that a magnetic attraction force arises between the first portion and the at least one first permanent magnet, the magnetic attraction force pulling the at least one sliding door or pivoting/sliding door by the offset into the open position.       

     The first portion then forms the magnetically more conductive portion than the second portion. 
     The difference in the magnetic conductivity between the first portion and the second portion can be produced by a different volume, a different area, a different mass of magnetically conductive material and/or by a different magnetic air gap with respect to the at least one first permanent magnet. 
     In particular, between the at least one first permanent magnet and the first portion, on the one hand, and the second portion, on the other hand, as seen in a plane perpendicular to the sliding direction of the at least one door or pivoting/sliding door, there can be a different distance d in each case which then, in an overlapping position between the at least one first permanent magnet and the first portion or between the at least one first permanent magnet and the second portion, forms a magnetic air gap of different size in each case. For example, the first portion then protrudes over the second portion, as seen in the plane perpendicular to the sliding direction of the at least one door or pivoting/sliding door and is directed toward the at least one first permanent magnet. A magnetic attraction force between the at least one permanent magnet and the first portion is then also produced because, in a first overlapping position of the least one permanent magnet with the first portion, a first magnetic air gap is smaller than a second magnetic air gap which is formed in a second overlapping position of the at least one permanent magnet with the second portion. 
     The second portion can also have at least one recess or a through opening in a magnetically conductive material of a wall of the door frame or of the door guide or of the first element arranged on the door frame or on the door guide, or of a wall of the at least one sliding door or pivoting/sliding door, or of the second element arranged on the at least one sliding door or pivoting/sliding door. 
     Furthermore, the first portion can have at least one local accumulation of magnetically conductive material on a wall of the door frame or on the door guide or on a first element arranged on the door frame or on the door guide, or on a wall of the at least one sliding door or pivoting/sliding door or on a second element arranged on the at least one sliding door or pivoting/sliding door. A local accumulation of magnetically conductive material means that a greater mass, a greater volume or a greater area of magnetically conductive material is located there than in the regions adjacent to the local accumulation. 
     The first element and/or the second element can be fastened here to the door frame or to the door guide or to the at least one sliding door or pivoting/sliding door in any manner and direction. 
     The at least one permanent magnet and the at least one magnetically conductive element can also be brought into at least a partial overlap, as seen in a direction perpendicular to the at least one sliding door, in the closed position or in an intermediate position of the at least one sliding door or pivoting/sliding door. In the at least partial overlap, then, for example, the magnetic resistance of the magnetic flux between the at least one first permanent magnet and the at least one magnetically conductive element can be minimal. 
     The distance between the at least one first permanent magnet and the at least one magnetically conductive element, as seen in the plane perpendicular to the sliding direction of the at least one door or pivoting/sliding door, can also be different, firstly in the closed position and secondly in an intermediate position, which is arranged adjacent to the closed position, of the least one door, the distance then forming an air gap in an overlapping position of the at least one first permanent magnet with the at least one magnetically conductive element. In particular, the difference can be smaller in the intermediate position than in the closed position, and therefore, in the emergency-unlocked state, a magnetic attraction force attracts the at least one sliding door or pivoting/sliding door from the closed position in the direction of the intermediate position. 
     The at least one magnetic conductive element can also be formed by at least one second permanent magnet. 
     According to a development of this measure, the at least one first permanent magnet and the at least one second permanent magnet can then be arranged on the door frame or on the door guide and on the at least one sliding door or pivoting/sliding door or connected to the assemblies in such a manner that a magnetic attraction force acts between unlike poles of the first and second permanent magnets (between North Pole and South Pole), the magnetic attraction force pulling the at least one sliding door or pivoting/sliding door for at least a distance in the direction of the open position in the emergency-unlocked state. 
     Alternatively, if the at least one magnetic conductive element is formed by a second permanent magnet, the at least one first permanent magnet and the at least one second permanent magnet can then be arranged on the door frame or on the door guide and on the at least one sliding door or pivoting/sliding door or can be connected to the assemblies in such a manner that a magnetic repulsion force acts between like poles of the first and second permanent magnets (e.g., between North Pole or between North Pole and between South Pole and South Pole), the magnetic repulsion force forcing the at least one sliding door for a distance in the direction of the open position in the emergency-unlocked state. 
     Disclosed embodiments also relate to a vehicle, for example, a rail vehicle having at least one above-described vehicle door assembly. 
       FIG. 1  shows a schematic side view of a sliding door assembly  1  of a rail vehicle as an optional embodiment of a vehicle door assembly. The sliding door assembly  1  may be designed here in single leaf form with just one door leaf or just one sliding door  2 . Alternatively, disclosed embodiments can also be used in the case of a multi-leaf and, for example, two-leaf sliding door assembly with two sliding doors. 
     The sliding door assembly  1  here has a sliding door  2  which is slidable in relation to a door frame  6 , which has a door opening  4 , in a sliding direction symbolized by the double arrow  8 , shown by a dashed line in  FIG. 1 . In addition, the sliding door assembly  1  comprises, for example, an electrical drive device which is not shown here for clarity reasons and by which the sliding door  2  is movable into a closed position closing the door opening  4  and into an open position opening up the door opening  4  and into any desired intermediate positions between the closed position and the open position. 
     Furthermore, the sliding door assembly  1  also comprises, for example, an electrical locking device  10  for locking the sliding door  2  at least in the closed position, with an emergency unlocking device  12 , by which the at least one sliding door  2 , which is locked in the closed position, can be unlocked in the event of an emergency. The emergency unlocking device  12  may be actuable purely mechanically, for example, via a cable pull mechanism operable by hand, and therefore no current is required for the unlocking in the event of an emergency. In the exemplary embodiment shown, in the closed position ( FIG. 1 ), a first vertical sliding door edge or a closing edge  14  of the sliding door  2  enters into contact with a first vertical frame part  16  of the door frame  6 . In the closed position, the second vertical sliding door edge  18  overlaps a second vertical frame part  20  of the door frame  6 , which frame part is shown in  FIG. 1  by a dashed line, and therefore the door opening  4  between the two vertical frame parts  16 ,  20  and horizontal frame parts (not shown here) of the door frame  6  is completely closed. 
     The sliding door  1  is mounted slidably in the sliding direction  8  on a door guide  22 , wherein the door guide  22  here includes, for example, an upper carrier plate  24  which is held on a body  26  of the rail vehicle. Furthermore, the upper carrier plate  24  is arranged parallel to an upper horizontal frame part of the door frame  6 . In addition to the upper carrier plate  24 , the door guide  22  can also have further carrier elements by which the sliding door  2  is mounted slidably on the body  26 . 
     Not least, an emergency opening device is provided for the at least partial emergency opening of the sliding door in the emergency-unlocked state. The emergency opening device includes a currentlessly acting magnetic device  28  which, when the sliding door  2  is located in the closed position shown in  FIG. 1  and has been unlocked in the event of an emergency by the emergency unlocking device  12 , a magnetic force generated without the action of electrical current is exerted on the sliding door  2  in such a manner that the sliding door  2  is pushed or pulled for at least a distance in the direction of the open position from the closed position. 
     In the exemplary embodiment of  FIG. 1 , the magnetic device  28  includes a first permanent magnet  30  and a magnetically conductive element  30 , wherein the first permanent magnet  30  is fastened statically, for example, to the sliding door  2  and the magnetically conductive element  32  is fastened statically, for example, to the door guide  22 . However, the reverse arrangement of first permanent magnet  30  and magnetically conductive element  32  is also conceivable, and therefore the first permanent magnet  30  is then fastened statically to the door guide  22  and the magnetically conductive element  32  is fastened statically to the sliding door  2 . 
     The upper carrier plate  24  forming at least part of the door guide  22  here has here, for example, an approximately Z-shaped cross section, wherein a first limb  34  of the carrier plate  24  that runs in a horizontal plane forms a flat roller track for rollers  36  which are held on connecting parts  38  so as to be rotatable about axes of rotation  40  which are oriented perpendicularly to the plane of the sliding door  2 . The connecting parts  38  connect the rollers  36  to the sliding door  2 , and therefore the sliding door  2  is slidable or rollable via the rollers  36  in the sliding direction  8  in relation to the door frame  6  and along the carrier plate  24 . The door guide  22  can alternatively also be designed as a recirculating ball bearing guide. Furthermore, the upper carrier plate  24  can also have a U-shaped cross section. 
     A second limb  42 , which is oriented approximately vertically in the use position, of the carrier plate  24  bears the magnetically conductive element  32 , for example, in the form of, for example, a cubic body which is composed of magnetically conductive ferromagnetic material. The third limb  44  of the carrier plate  24  is connected to the body  26  of the rail vehicle. The relatively small wall thickness of the carrier plate  24  itself means that it is less magnetically conductive than the magnetically conductive element  32 . The magnetically conductive element  32  consequently forms a type of “accumulation” of magnetically conductive material in relation to the carrier plate  24 . In particular, the magnetically conductive element  32  forms part of the carrier plate  42  and is composed of the same magnetically conductive ferromagnetic material as the latter. 
     In the present example, two rollers  36  each having a connecting part  38  are present on a horizontal sliding door edge, which is at the top in the use position, in each case on the end side, e.g., in the region of the two vertical sliding door edges  14 ,  18 . On the roller  36  which faces the vertical first frame part  16  of the door frame  6 , on which a frame-side part of the locking device  10  is formed, for example, opposite the connecting part  38 , there is a supporting part  46  which is connected to the connecting part  38  and therefore also to the sliding door  2 . The roller  36  is then mounted rotationally, for example, on the connecting part  38  and the supporting part  46 . The supporting part  46  here bears, for example, the first permanent magnet  30 . As seen in a direction perpendicular to the plane of the sliding door  2 , the first permanent magnet  30  which is fastened to the sliding door  2  overlaps the magnetically conductive element  32 , which is fastened to the carrier plate  24 , in an intermediate position between the closed position and the open position of the sliding door  2 . In the intermediate position, the sliding door  2  is then open by an offset X. 
     By contrast, in the closed position of the sliding door  2  that is shown in  FIG. 1 , the first permanent magnet  30  which is connected to the sliding door  2  is offset by the offset X in relation to the magnetically conductive element  32  on the carrier plate  24 , as seen in the sliding direction  8  of the sliding door  2 , wherein the offset X of the magnetically conductive element  32  extends in the direction of the open position from the first permanent magnet  30 . 
     The case will now be assumed below in which there has been a current failure at the rail vehicle and then the sliding door  2  cannot be unlocked as customary by electrical actuation of the locking device  10  in the closed position in order then to be brought into the open position by the drive device. To the contrary, the emergency locking device  12  which is operative even currentlessly is then used for unlocking the sliding door in the closed position. 
     In the closed position of the emergency-unlocked sliding door  2 , a magnetic force in the form of a magnetic reluctance force  48  then acts between the first permanent magnet  30  and the magnetically conductive element  32  in such a manner or in such a direction that the magnetic resistance of the magnetic flux between the first permanent magnet  30  and the magnetically conductive element  32  is reduced. Consequently, in the case of the example described here, the magnetic reluctance force  48  in the form of an attraction force acts between the first permanent magnet  30  and the magnetically conductive element  32 , which is arranged offset with respect thereto by the offset X in the sliding direction, because here, for example, the carrier plate  24  has a substantially lower magnetic conductivity than the magnetically conductive element  32 , and the magnetic reluctance force  48  now attempts to reduce the magnetic resistance by moving the first permanent magnet  30  toward the magnetically conductive element  32 . 
     In addition, the reluctance force  48  arises because the magnetically conductive element  32  is arranged on the carrier plate in a manner protruding in the direction of the first permanent magnet  30  and then, as is easily conceivable with reference to  FIG. 2 , between the first permanent magnet  30  and the magnetically conductive element  32 , as seen in the plane perpendicular to the sliding direction of the door  2 , the distance d between the first permanent magnet  30  and the magnetically conductive element  32  becomes minimal in the overlapping position. This distance d forms a magnetic air gap between the first permanent magnet  30  and the magnetically conductive element  32 . In the overlapping position of the first permanent magnet  30  with the magnetically conductive element  32 , the magnetic air gap is then smaller than in non-overlapping positions deviating therefrom and, for example, in the closed position, and therefore, in the overlapping position, the magnetic resistance is at the lowest and the magnetic conductivity at the highest. 
     The magnetic reluctance force  48  acting on the sliding door  2  is symbolized in  FIG. 1  by the solid-line arrow. The magnetic reluctance force  48  then moves the emergency-unlocked sliding door  2  in the opening direction until the first permanent magnet  30  on the sliding door  2  overlaps the magnetically conductive element  32  on the carrier plate  24  of the door guide  22 , the magnetic resistance, in this position, being minimal in the sliding direction  8  and then a magnetic reluctance force  48  no longer acting at least in the sliding direction  8 . 
     The offset X between the first permanent magnet  30  and the magnetically conductive element  32  in the sliding direction corresponds to a desirably arising gap between the first vertical frame part  16  of the door frame  6  and the first vertical sliding door edge  14 , the gap coming about by the magnetic reluctance force  48  in the overlapping position between first permanent magnet  30  and magnetically conductive element  32 . The position of the sliding door  2  then corresponds to an intermediate position between the closed position and the open position. This gap makes it possible for a person to be able to reach with their fingers into the gap and then move the sliding door  2  by hand from the intermediate position into the open position, in order, for example, to be able to exit from the rail vehicle. Since the driving device is not capable of applying any counterforces in the event of the current failure assumed here, this can be brought about without great effort. 
     The difference of the further embodiment of  FIG. 3  and  FIG. 4  over the embodiment of  FIG. 1  and  FIG. 2  include a magnetically conductive element  32  which is fastened to the carrier plate  24  is formed by a second permanent magnet which then, in the closed position of the sliding door  2 , likewise has an offset X with respect to the first permanent magnet  30  which is fastened to the sliding door  2 . The polarization of the first permanent magnet  30  and of the second permanent magnet  32  is then such that, in the overlapping position shown in  FIG. 4 , unlike poles (North Pole and South Pole) lie opposite one another such that, in the closed position, a magnetic attraction force acts as reluctance force  48  between the two permanent magnets  30 ,  32  which pull the sliding door  2  in the direction of the open position by the offset X in the emergency-unlocked position. 
       FIG. 5  shows a sectional illustration through a sliding door assembly  1  according to a further embodiment, with the sliding door  2  being in the closed position. In this embodiment, the sliding door  2  likewise bears the first permanent magnet  30 . In the closed position, a local through opening  50  is formed in the wall of the second limb  42  of the carrier plate  24  opposite the first permanent magnet  30 . 
     Consequently, in the closed position, the first permanent magnet  30  approximately overlaps the through opening  50 , with the magnetic resistance being relatively large. In order to reduce the magnetic resistance, a magnetic reluctance force  48  then arises which attempts to pull the first permanent magnet  30  together with the sliding door  2  in the direction of higher magnetic conductivity. Since, however, the carrier plate  24  is, for example, magnetically conductive, the reluctance force  48  acts in the sliding direction  8  toward the edge of the through opening  50  in the carrier plate  24  and therefore in the opening direction of the sliding door  2 . The first portion of the carrier plate  24  which, as seen in the sliding direction  8 , adjoins the through opening  50  and, in the closed position, is arranged offset by the offset X in relation to the first permanent magnet  30 , then forms an “accumulation” of magnetically conductive material in relation to a second portion of the carrier plate, which portion is then formed by the through opening  50  which, by contrast, has only very small magnetic conductivity (air), if any at all, which corresponds to a “reduction” of magnetically conductive material in the region of the through opening  50 . 
     The magnetic reluctance force  48  which moves the sliding door in the direction of the open position is therefore based on a difference in the magnetic conductivity between the first portion of the carrier plate  24  in the form of the uninterrupted wall of the carrier plate  24  and the second portion of the carrier plate  24  in the form of the through opening  50  of the carrier plate  24 , wherein, as seen in the sliding direction  8 , in the closed position the first and second portions are arranged one behind the other and are offset by the offset X in relation to one another. The difference in the magnetic conductivity between the first portion and the second portion of the carrier plate  24  can therefore be produced by a different volume, a different area, a different mass of magnetically conductive material and/or by a different magnetic air gap d. 
     According to a further exemplary embodiment, not illustrated here, the magnetically conductive element  32  is likewise formed by a second permanent magnet which is fastened, for example, in turn to the carrier plate  24 . The first permanent magnet  30  is likewise fastened again to the sliding door  2 , wherein the first permanent magnet  30  and the second permanent magnet  32  overlap in the closed position of the sliding door  2 , but then with like poles lying opposite one another, e.g., North Pole and North Pole or South Pole and South Pole. Consequently, in the closed position of the sliding door  2 , a magnetic repulsion force acts between the like poles, the magnetic repulsion force then pushing the sliding door  2  for a distance in the direction of the open position in the emergency-unlocked state. 
     Instead of being fastened to the carrier plate  24  or to the door guide  22 , the magnetically conductive element  32  or the second permanent magnet  32  could also be fastened to the door frame  6  in such a manner that a magnetic reluctance force  48  is produced in the form of a magnetic attraction or repulsion force which pulls or pushes the sliding door  2  at least for a distance into the open position from the closed position. 
     Furthermore, it does not matter whether the first permanent magnet  30  is statically connected to the sliding door  2  and the magnetically conductive element  32  or the second permanent magnet  32  to the door frame  6  or to the door guide  22 . The conditions may also be reversed. 
     The above-described principle of opening a sliding door  2  of a sliding door assembly  1  in the event of an emergency with the aid of a magnetic reluctance force  48  can readily also be transferred to a pivoting/sliding door assembly with at least one pivoting/sliding door, with the sole difference consisting in that a pivoting/sliding door from the closed position first of all executes a pivoting movement which then merges later into a pure sliding movement. The first permanent magnet  30  and the magnetically conductive element  32  can then be correspondingly arranged such that the direction of the magnetic force or of the reluctance force  48  acts in the pivoting direction in order to achieve the desired partial opening of such a pivoting/sliding door. 
     LIST OF REFERENCE SIGNS 
     
         
           1  Sliding door assembly 
           2  Sliding door 
           4  Door opening 
           6  Door frame 
           8  Sliding direction 
           10  Locking device 
           12  Emergency unlocking device 
           14  First vertical sliding door edge 
           16  First vertical frame part 
           18  Second vertical sliding door edge 
           20  Second vertical frame part 
           22  Door guide 
           24  Upper carrier plate 
           26  Body 
           28  Magnetic device 
           30  First permanent magnet 
           32  Magnetically conductive element 
           34  First limb 
           36  Rollers 
           38  Connecting part 
           40  Axis of rotation 
           42  Second limb 
           44  Third limb 
           46  Supporting part 
           48  Reluctance force 
           50  Through opening 
         X Offset