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CROSS-REFERENCE TO PRIOR APPLICATIONS 
       [0001]    This application is a U.S. National Phase Application under 35 U.S.C. §371 of International Application No. PCT/EP2015/055350, filed on Mar. 13, 2015, and claims benefit to Utility Model Application No. DE 20 2014 002 413.8, filed on Mar. 18, 2014. The International Application was published in German on Sep. 24, 2015 as WO 2015/140078 under PCT Article 21(2). 
     
    
     FIELD 
       [0002]    The invention relates to a door arrangement, in particular a house or balcony door arrangement, comprising a door leaf which can be moved relative to a frame, having a locking device which in a locked state locks the door leaf to the frame by at least one locking element, and which in an unlocked state releases the door leaf relative to the frame, wherein an actuating element which can be actuated mechanically by an operator is provided to select the state of the locking device, and wherein, in order to transmit a movement of the actuating element to the at least one locking element, the locking device has a traction rod or driving rod which is arranged displaceably on the door leaf, wherein a motor-driven drive unit for driving the traction rod or driving rod is provided. 
       BACKGROUND 
       [0003]    A door arrangement of this type has become known under the name “GU-SECURY Automatic mit A-Öffner” [“GU-SECURY Automatic with A-Opener”] by the applicant Gretsch-Unitas GmbH Baubeschläge, Johann-Maus-Straβe 3, 71254 Ditzingen. The already-known door arrangement has the advantage that the motor-driven drive unit provides an additional possible way of driving the traction rod or driving rod, so that a locking state of the locking device can be changed independently of an actuating state of the actuating element (for example a follower or a closing cylinder). In this manner, remote control of the locking device can be realized, for example in order to unlock the street door of an apartment building by a control unit provided in the apartment. 
         [0004]    It is an object of the invention to further improve the operating comfort of the already-known door arrangement. 
       SUMMARY 
       [0005]    This object is achieved according to the invention in that a sensor device for the contactless detection of a movement of the traction rod or driving rod is provided and in that the motor-driven drive unit can be activated dependent on a movement of the traction rod or driving rod detected by the sensor device. 
         [0006]    In the context of the invention, it has been recognized that in unfavorable conditions it may happen that operation of the actuating element independent of the motor-driven drive unit is accompanied by increased operating forces. According to the invention, it has furthermore been recognized that the traction rod or driving rod is moved upon actuation of the actuating element and that this movement can be detected. The detection of the movement of the traction rod or driving rod takes place in contactless manner, so that the detection of movement as such does not itself contribute to increasing the operating forces necessary for operation of the actuating element. Furthermore, it has been recognized according to the invention that the operating forces for displacing the traction rod or driving rod upon an initial movement of the traction rod or driving rod out of an idle position are still comparatively low, at any rate as long as such a movement of the traction rod or driving rod is not yet effective for changing the locking state of the at least one locking element. Finally, it has been recognized according to the invention that a further movement, succeeding the initial movement, of the traction rod or driving rod can take place in that the drive device already present (for example for the purpose of remote control) is activated and thus the subsequent movement of the traction rod or driving rod which is effective for changing the locking state of the at least one locking element is brought about by the motor-driven drive. This motor-driven driving of the traction rod or driving rod can take place in particular independently of an actuating state of the actuating element, so that a change in the locking state of the at least one locking element takes place exclusively by the action of the motor-driven drive and without operating forces having to be exerted on the operating element. 
         [0007]    Overall, a very comfortably operable door arrangement is provided which is suitable in particular also for stiff locking devices. 
         [0008]    In a preferred embodiment of the invention, provision is made for a first part of the sensor device to be formed by a portion of the traction rod or driving rod and for a second part of the sensor device to be arranged fixed to the door leaf. This has the advantage that movement of the traction rod or driving rod can be detected directly without the traction rod or driving rod having to be changed or converted by an additional sensor part. This is advantageous in particular with regard to the fact that already-known systems referred to first hereinbefore can be retrofitted in a simple manner. 
         [0009]    The portion of the traction rod or driving rod which forms the first part of the sensor device is preferably a material recess or material cutout in the traction rod or driving rod, in particular in the form of an elongate hole pocket or elongate hole aperture. Such material recesses or material cutouts are provided in already-known and conventional traction rods or driving rods in order to screw the lock in the door leaf and nevertheless to permit free movement of the traction rod or driving rod between the faceplate and door leaf. Advantageously, elongate hole pockets or elongate hole apertures can therefore be used without any modification of the already-known traction rods or driving rods being necessary. This too provides a particularly simple possibility of retrofitting for already-known systems referred to first hereinbefore. 
         [0010]    A more preferred embodiment of the invention provides for the second part of the sensor device to be in the form of a coil for generating a magnetic field which is changeable dependent on the position of the traction rod or driving rod. A coil of this type permits the use of a non modified traction rod or driving rod described above. As a result, a contactless sensor device can be provided which furthermore is not susceptible to disruption, for example due to dirt. 
         [0011]    Additionally or alternatively to the use of a coil, the second part of the sensor device is in the form of an optical sensor. 
         [0012]    Further, it is advantageous if the second part of the sensor device and the motor-driven drive are arranged in a common housing. 
         [0013]    This has the advantage that the motor-driven drive of an already-known system referred to first hereinbefore can be exchanged in a simple manner, without additional installation space having to be provided for the second part of the sensor device. This too makes simple retrofitting possible. 
         [0014]    The invention is advantageous in particular when the locking device comprises a plurality of locking elements which cooperate with the traction rod or driving rod. Such locking devices provide a greater degree of security against break-ins in particular for external doors of buildings; the use of a plurality of locking elements is however accompanied by an increase in the operating force necessary for the actuation of the locking elements as a whole. Therefore it is particularly advantageous for a plurality of locking elements if the motor-driven drive unit, once an initial movement of the traction rod or driving rod has been detected, brings about the further, subsequent movement of the traction rod or driving rod and thus drives the locking elements independently of the actuating element which can be actuated by the operator. 
         [0015]    The activation of the motor-driven drive unit dependent on a movement of the traction rod or driving rod which is detected by the sensor device preferably takes place for the purpose of transferring the locking device out of the locked state into the unlocked state, in particular exclusively for the purpose of transferring the locking device out of the locked state into the unlocked state, and not for the purpose of transferring the locking device out of the unlocked state into the locked state. This has the advantage that a possibility of unlocking the locking device which is desired for safety reasons can be triggered by initial low operating forces on the actuating element. This is advantageous in particular when the operator is a child or a frail person. 
         [0016]    In the event that the motor-driven drive unit does not serve to transfer the locking device out of the unlocked state into the locked state, it is preferred for the motor-driven drive unit to transfer the traction rod or driving rod by a pressure force transmission unit in an opening direction out of the locked state into the unlocked state, and for the motor-driven drive unit to be uncoupled from the traction rod or driving rod in a closing direction which is opposed to the opening direction. In this manner, it is possible for unlocking of the locking device to take place by the motor-driven drive unit, but in the event of a power failure and failure of the motor-driven drive unit for the traction rod or driving rod nevertheless—upon application of the operating forces necessary for unlocking, but not counter to self-locking of the motor-driven drive unit—to be able to be actuated both in the opening direction for unlocking the locking device and in the closing direction for locking the locking device. The motor-driven drive unit is therefore then effective only in the opening direction, and in the closing direction is not coupled with the traction rod or driving rod. 
         [0017]    When using an abovementioned pressure force transmission unit, it is more preferable for an initial movement of the traction rod or driving rod which is brought about by the actuating element to be accompanied by an idle stroke of the traction rod or driving rod which ends with a force uptake surface of the traction rod or driving rod, following on from the idle stroke, coming to lie against a force transmission surface of the motor-driven drive unit. In this manner, it is ensured that an initial movement of the traction rod or driving rod is in each case uninfluenced by self-locking of the motor-driven drive unit. 
         [0018]    In a further preferred embodiment of the invention, provision is made for a first part of the sensor device to be formed by an additional element coupled for movement with the traction rod or driving rod, and for a second part of the sensor device to be arranged fixed to the door leaf. The use of an additional element has the advantage that it can be optimized with regard to particularly reliable and accurate detection of a movement of the additional element. Advantageously, the additional element has exclusively the above-mentioned functions. This permits simple retrofitting of an additional element on existing installations. 
         [0019]    It is possible for the additional element and the traction rod or driving rod to be connected together firmly and immovably relative to each other, for example by a positive and/or non-positive connection. 
         [0020]    It is however preferred if the additional element and the traction rod or driving rod are coupled together such that the traction rod or driving rod upon movement in a first direction of movement drives the additional element, and that the additional element upon movement of the traction rod or driving rod is uncoupled from the traction rod or driving rod in a second direction of movement which is opposed to the first direction of movement. This can for example be achieved in that the additional element has an entraining portion which cooperates with only one limitation of a material recess or material cutout (in particular in the form of an elongate hole pocket or elongate hole aperture) formed in the traction rod or driving rod. Preferably the first direction of movement corresponds to unlocking of the locking device (“opening direction”), while the second direction of movement corresponds to locking of the locking device (“closing direction”). 
         [0021]    In the event that the additional element is not coupled with the traction rod or driving rod in both directions of movement thereof which are opposed to each other, it is advantageous to provide a restoring device which transfers the additional element out of a deflected position (into which the additional element has been brought by the traction rod or driving rod) back into a basic position. The restoring device may for example comprise a compression spring or tension spring. 
         [0022]    Further, it is preferred if the second part of the sensor device is in the form of a coil or other suitably formed electrical conductor for generating an electrical, magnetic or electromagnetic field which changes dependent on the position of the additional element. In particular, precisely one and only one coil, or precisely one and only one suitably formed electrical conductor is provided. A coil or a suitably formed electrical conductor permits detection of a movement and/or ascertaining of a position of the additional element. As a result, a contactless sensor device can be provided which furthermore is not susceptible to disruption, for example due to dirt. 
         [0023]    The additional element is preferably at least in portions, in particular as a whole, made from a ferromagnetic material, in particular iron. Such a material influences a magnetic field, the properties of which vary from the point of view of the second part of the sensor device upon displacement of the additional element, so that a movement of the additional element can be detected and/or a position of the additional element can be ascertained. 
         [0024]    Independently of the use of an additional element, additionally or alternatively to the use of a coil or other suitably formed electrical conductor as the second part of the sensor device, other sensors may also be used, for example an optical sensor and/or a capacitive sensor which detects the change in an electrical field. 
         [0025]    Likewise independently of the use of an additional element, in a departure from the feature named in claim  1  “sensor device for the contactless detection of a movement . . . ” it is also possible to use a sensor device which is not contactless. Examples of such non-contactless sensor devices are named below for an electrical sensor and for a mechanical sensor. 
         [0026]    Likewise, as the second part of the sensor device the use of an electrical sensor (for example a potentiometer) which detects the change in electrical parameters (for example resistance, voltage, current, eddy currents) is possible. 
         [0027]    A mechanical sensor, for example a microswitch, can also be used as the second part of the sensor device. 
         [0028]    Further, it is advantageous if the second part of the sensor device and the motor-driven drive are arranged in a common housing. This has the advantage that the motor-driven drive of an already-known system referred to first hereinbefore can be exchanged in a simple manner, without additional installation space having to be provided for the second part of the sensor device. This too makes simple retrofitting possible. In particular, it is preferred if the additional element and/or a restoring device described above is or are also arranged and/or mounted on or in the housing. 
         [0029]    It is more preferable if the additional element has at least two material portions which are adjacent to each other, viewed in the direction of movement of the additional element, which portions have different dimensions from each other, viewed transversely to the direction of movement of the additional element. Therefore in each case more or less material is made available at the level of the material portions which are adjacent to each other, for example by varying the material thickness and/or material height of the material portions. In the event that the material portions are produced from an electrically and/or magnetically conductive material, the second part of the sensor device can detect a different electric, magnetic or electromagnetic field strength or field pattern for a smaller material portion compared with a field strength or a field pattern for a larger material portion. 
         [0030]    A preferred embodiment of the invention provides for the additional element to have at least one land extending in the direction of movement of the additional element, which land has at least one margin which is stepped or arranged inclined relative to the direction of movement. Different positions of the additional element can be detected corresponding to the number of steps; in the case of a margin which is arranged inclined, even a number of positions of the additional element which corresponds to the resolution of the sensor device can be detected. In the simplest case, however, in each case a movement of the additional element can be detected. 
         [0031]    It is likewise conceivable to detect the movement and/or the position of the additional element by its partial arrangement within an electrical, magnetic or electromagnetic field which is generated by a coil or by another suitably formed electrical conductor. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         [0032]    The present invention will be described in even greater detail below based on the exemplary figures. The invention is not limited to the exemplary embodiments. All features described and/or illustrated herein can be used alone or combined in different combinations in embodiments of the invention. The features and advantages of various embodiments of the present invention will become apparent by reading the following detailed description with reference to the attached drawings which illustrate the following: 
           [0033]      FIG. 1 : a perspective view of an embodiment of a door arrangement; 
           [0034]      FIG. 2 : a detail designated II in  FIG. 1  in an enlarged exploded view; 
           [0035]      FIG. 3 : the detail of  FIG. 2  in a side view; 
           [0036]      FIG. 4 : a perspective view of a detail, which corresponds substantially to  FIG. 2 , of a further embodiment of a door arrangement, comprising an additional element; 
           [0037]      FIG. 5 : a side view of the additional element; and 
           [0038]      FIG. 6 : a plan view of the additional element. 
       
    
    
     DETAILED DESCRIPTION 
       [0039]    An embodiment of a door arrangement is designated as a whole by the reference numeral  10  in the drawing. The door arrangement  10  comprises a door leaf  14  which can be moved, for example can be pivoted, relative to a frame. A locking device  16  is provided for locking the door leaf  14  to the frame  12 , which device in the embodiment illustrated comprises two locking elements  18 ,  20 . Actuation of the locking device  16  can take place by an actuating element  22 , for example in the form of a closing cylinder  24 . It is also possible for a door handle (not shown) to form an actuating element  22  which cooperates with a follower hub  26 . 
         [0040]    In the embodiment illustrated in the drawing, the actuating element  22  and/or the follower hub  26  is/are part of a lock case  28 . It is possible for the lock case  28  to comprise a bolt  30  which is actuated directly by the actuating element  22 , in particular in the form of the closing cylinder  24 . The lock case  28  may, in addition or alternatively to a bolt  30  also comprise a latch bolt  32  which is actuated directly by an actuating element  22  in the form of a door handle using the follower hub  26 . 
         [0041]    In order to transmit a movement of the actuating element  22  to the locking elements  18 ,  20  a traction rod or driving rod  34  is provided which is overlaid by a faceplate  36  in a state mounted on the door leaf  14 . In particular, the traction rod or driving rod  34  and the faceplate  36  extend along a vertically oriented side of the door leaf  14  which is remote from the hinge plate. 
         [0042]    The door arrangement  10  further comprises a motor-driven drive unit which is designated as a whole by the reference numeral  38 , by which the traction rod or driving rod  34  can be driven in particular directly, preferably exclusively in an opening direction  40  of the traction rod or driving rod  34  which is indicated in  FIG. 3 . 
         [0043]    The motor-driven drive unit  38  comprises a motor arranged within a housing  42 , by which motor a drive element  44  can be moved in the opening direction  40  of the traction rod or driving rod  34 , and in the opposite direction thereto. The drive element  44  has a force transmission surface  46  which in a locked state of the locking device  16  is spaced apart by an idle stroke  48  from a force uptake surface  50  of a force uptake element  52  which is connected in positive and/or non-positive manner to the traction rod or driving rod  34 . 
         [0044]    The motor-driven drive unit  38  can be connected securely to the faceplate  36  by screws  54 . In such case, it is preferable for the motor-driven drive unit  38  to comprise projections  56  which penetrate material apertures  58 , in particular designed as elongate hole apertures, in the traction rod or driving rod  34 . In such case, a front side of the projections  56  which faces the rear side of the faceplate  36  protrudes over a front side  60  of the traction rod or driving rod  34 , so that the motor-driven drive unit  38  on one hand can be connected securely to the faceplate  36  and on the other hand permits free movement of the traction rod or driving rod  34  between the motor-driven drive unit  38  and the faceplate  36 . 
         [0045]    The door arrangement  10  further comprises a sensor device  62  for contactless detection of a movement of the traction rod or driving rod  34 . The sensor device  62  comprises a first sensor part  64  which is formed by a portion  66  of the traction rod or driving rod  34 . 
         [0046]    A second part  68  of the sensor device  62  is arranged fixed to the door leaf, and therefore does not move jointly with the traction rod or driving rod  34 . The second part  68  of the sensor device  62  is advantageously a coil  70  which generates a magnetic field  72  indicated in  FIG. 3  when a current flows through it. An embodiment with two coils  70  is illustrated in the drawing; in another embodiment, merely one coil  70  is provided. 
         [0047]    The magnetic field  72  of a or the coil  70  is changed by changing the position of the traction rod or driving rod  34 , namely in that in the course of a movement of the traction rod or driving rod  34  the degree of coverage of the material aperture  58  which is in the form of an elongate hole relative to the coil  70  changes. The change in the magnetic field  72  brings about a change in a current flowing through the coil  70 . This change is detected by a control unit and on exceeding a specifiable threshold value is used to activate the motor of the motor-driven drive unit  38 . 
         [0048]    Starting from a closed state of the door leaf  14 , in which the door leaf  14  lies against the frame  12 , and starting from a locked state of the locking device  16 , in which the locking elements  18  and  20  lock the door leaf  14  to the frame  12 , actuation of the actuating element  22  by an operator causes the traction rod or driving rod  34  to be moved starting from the state illustrated in  FIG. 3 . Due to the idle stroke  48 , in such case the traction rod or driving rod  34  can be moved counter to the force of gravity (i.e. upwards); it is sufficient for the traction rod or driving rod  34 , starting from its rest position, to be displaced at all and in so doing for the relative position of the material aperture  58  of the traction rod or driving rod  34  relative to the coil  70  to change. The change in the magnetic field  72  which is detectable thereby is used by the control unit of the motor-driven drive unit  38  to activate the motor. 
         [0049]    Once the idle stroke  48  or part of the idle stroke  48  has been overcome and the force transmission surface  46  has subsequently come to lie against the force uptake surface  50 , further driving of the drive element  44  brings about a movement of the traction rod or driving rod  34  in the opening direction  40 . In this manner, the locking elements  16 ,  18  are unlocked in a manner known per se; in such case, operating forces on the actuating element  22  can be dispensed with entirely. 
         [0050]    Once the locking device  16  has been released, the door leaf  14  can be opened. 
         [0051]    The locking elements  18 ,  20  are for example spring-actuated latch bolts. Transferring of the traction rod or driving rod  34  counter to the opening direction  40  can take place by the spring actuation and/or by the traction rod or driving rod  34  being displaced downwards due to its own weight. 
         [0052]    The housing  42  is provided spatially separated from the lock case  28 . This simplifies retrofitting of an existing installation. 
         [0053]    The magnetic field  72  is in particular an electromagnetic field. 
         [0054]      FIG. 4  illustrates an assembly which can be used instead of the components illustrated in  FIG. 2 . In  FIG. 4 , however, the traction rod or driving rod  34  and the faceplate  36  are not shown in order to improve clarity. The mode of operation of the assembly according to  FIG. 4  corresponds to the mode of operation described above with reference to  FIGS. 1 to 3 ; identical reference numerals are used for identical or functionally identical components. The assembly according to  FIG. 4  too comprises a housing  42  and a motor-driven drive  38 . The drive  38  has a motor  74  which cooperates with a drive element  44  (cf.  FIG. 2 ) via an actuator  76 . 
         [0055]    The assembly according to  FIG. 4  comprises an additional element designated as a whole by the reference numeral  78 , which is mounted displaceably on the housing  42 . The additional element  78  forms the first part  64  of the sensor device  62 . The second part  68  of the sensor device  62  is formed by a single coil  70 . 
         [0056]    The additional element  78  is in particular in the form of a metal part which is preferably produced by forming. The additional element  78  is produced in particular from a magnetic material. 
         [0057]    The additional element  78  has for example a material thickness  80  of approx. 0.5 mm to approx. 0.9 mm, in particular of approx. 0.7 mm (cf.  FIGS. 5 and 6 ). The additional element  78  has a main plane  82  and an additional plane  84 . The main plane  82  is arranged within the housing  42 . The additional plane  84  runs parallel to the main plane  82  and offset in the direction of the faceplate  36 . 
         [0058]    The main plane  82  has a reference portion  88  at a free end  86 . This portion comprises two lands  90 , which jointly delimit a gap  92 . The lands have margins  94  facing the gap  92 . The margins  94  are oriented inclined relative to a main direction of extent  96  of the additional element  78 , for example at an angle of approx. 5° to approx. 30°. 
         [0059]    The main direction of extent  96  of the additional element  78  corresponds to an axis along which the additional element  78  can be moved relative to the housing  42 . This axis runs parallel to an axis of movement of the traction rod or driving rod  34 . The axis of movement  42  is defined by the opening direction  40  and a closing direction which is opposed thereto. 
         [0060]    As a result of the margins  94  which are oriented inclined, the reference portion  88 , viewed in the direction of movement of the additional element  78 , has smaller material portions  98  and larger material portions  100  which are arranged adjacent to one another. These material portions preferably merge continuously into each other. 
         [0061]    The main portion  82  of the additional element  78  has on its end remote from the reference portion  88  an angled portion  102 , which together with a fixing device  104  (cf.  FIG. 4 ) fixed to the housing serves to arrange a restoring device  106  in the form of a tension spring  108 . 
         [0062]    The additional portion  84  has a entraining portion  110  which faces away outwards relative to the housing  42 , which portion cooperates with a (lower, in the drawing) limitation  112  of the material recess or material cutout  58 , formed in the traction rod or driving rod  34 , in the form of an elongate hole pocket or elongate hole aperture (cf.  FIG. 2 ). 
         [0063]    Upon a movement of the traction rod or driving rod  34  in the opening direction  40 , the limitation  112  of the material recess or material cutout  58  entrains the additional element  78  in the identical direction, so that the reference portion  88  moves relative to the coil  70 . This movement can be detected by the sensor device  62 , in order subsequently to activate the motor-driven drive unit  38 , so that a further movement of the traction rod or driving rod  34  is supported in a motor-driven manner. 
         [0064]    During the course of the displacement of the additional element  78 , the restoring device  106  is tensioned. If then the traction rod or driving rod is moved in a closing direction opposed to the opening direction  40 , the limitation  112  of the material recess or material cutout  58  lifts off from the entraining portion  110 . Returning of the additional element back into the non-deflected position takes place independently of the movement of the traction rod or driving rod  34  in that the energy stored in the restoring device  106  is released, in particular in that the tension spring  108  contracts. 
         [0065]    Moreover, for example with respect to the fastening of the housing  42  to the faceplate  36 , reference is made to the description relating to  FIGS. 1 to 3  for the embodiment illustrated in  FIGS. 4 to 6 . 
         [0066]    While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive. It will be understood that changes and modifications may be made by those of ordinary skill within the scope of the following claims. In particular, the present invention covers further embodiments with any combination of features from different embodiments described above and below. Additionally, statements made herein characterizing the invention refer to an embodiment of the invention and not necessarily all embodiments. 
         [0067]    The terms used in the claims should be construed to have the broadest reasonable interpretation consistent with the foregoing description. For example, the use of the article “a” or “the” in introducing an element should not be interpreted as being exclusive of a plurality of elements. Likewise, the recitation of “or” should be interpreted as being inclusive, such that the recitation of “A or B” is not exclusive of “A and B,” unless it is clear from the context or the foregoing description that only one of A and B is intended. Further, the recitation of “at least one of A, B and C” should be interpreted as one or more of a group of elements consisting of A, B and C, and should not be interpreted as requiring at least one of each of the listed elements A, B and C, regardless of whether A, B and C are related as categories or otherwise. Moreover, the recitation of “A, B and/or C” or “at least one of A, B or C” should be interpreted as including any singular entity from the listed elements, e.g., A, any subset from the listed elements, e.g., A and B, or the entire list of elements A, B and C.

Summary:
A door arrangement includes a door leaf movable relative to a frame. A locking device in a locked state locks the door leaf to the frame by at least one locking element and in an unlocked state releases the door leaf relative to the frame. An actuating element selects the state of the locking device. To transmit a movement of the actuating element, the locking device has a connecting bar which is arranged displaceably on the door leaf, wherein a motor-operated drive unit for driving the connecting bar is provided. A sensor device for the contactless detection of a movement of the connecting bar is provided and the motor-operated drive unit can be activated in accordance with a movement of the connecting bar detected by the sensor device.