Abstract:
A passenger seat for use in a motor vehicle includes a first and a second substantially planar region. The seat is pivotable about a horizontal axis between a first position and a second position. In the first position, the first region is horizontal and acts as the seat, and the second region is vertical and acts as the seat back, such that the passenger is facing forward. In the second position, the first region is vertical and acts as the seat back, and the second region is horizontal and acts as the seat, such that the passenger is facing backward.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority to, and the benefit of, European Patent Application No. EP08154258.1, filed in the European Intellectual Property Office on Apr. 9, 2008, the entire contents of which are incorporated herein by reference. 
       BACKGROUND OF THE INVENTION 
       [0002]    (a) Field of the Invention 
         [0003]    This invention relates to a passenger seat device for motor vehicles. 
         [0004]    (b) Description of the Related Art 
         [0005]    It is desirable, particularly in vehicles with three or more rows of seats, e.g. vans, for the passenger seats to be able to adopt several seat positions, e.g. forward-facing and backward-facing. 
         [0006]    Passenger seats which can be rotated about a vertical axis of rotation to alter the seat position are generally known. However, this solution requires a great deal of lateral space because the seats are generally longer than they are wide. 
         [0007]    The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art. 
       SUMMARY OF THE INVENTION 
       [0008]    A passenger seat for use in a motor vehicle includes a first and a second substantially planar region. The seat is pivotable about a horizontal axis between a first position and a second position. In the first position, the first region is horizontal and acts as the seat, and the second region is vertical and acts as the seat back, such that the passenger is facing forward. In the second position, the first region is vertical and acts as the seat back, and the second region is horizontal and acts as the seat, such that the passenger is facing backward. 
         [0009]    A bearing may pivotably mount the seat to the motor vehicle. The bearing may include two struts and a rail, slidably mounted in a corresponding rail on the floor of the motor vehicle. The struts may be mounted in the rail. 
         [0010]    A cushion may be mounted in the seat and movable such that in the first position, the cushion extends beyond an end of the second region and lies substantially flush with an end of the first region, and in the second position, the cushion extends beyond the end of the first region and lies substantially flush with the end of the second region. 
         [0011]    A headrest may be retractably mounted to an end of the each regions. 
         [0012]    At least one air cushion may be provided on each of the regions such that an amount of cushioning of each region can be adjusted. 
         [0013]    The seat may also include a seat belt reel device with a reelable seat belt at one side near where the regions meet, a first seat belt lock at another side near where the regions meet, a second seat belt lock near an end of the first region, and a third seat belt lock near an end of the second region. The seat belt may include first and second stop tongue parts each configured to be engaged in any of the seat belt locks. 
         [0014]    The seat may also include a receiving device on at least one of the regions for receiving a corresponding engaging device of an additional seat. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]      FIG. 1  is a schematic view of a motor vehicle seating arrangement according to an embodiment of this invention; 
           [0016]      FIGS. 2   a  and  2   b  are cross-sectional views of a motor vehicle floor rail according to an embodiment of this invention; 
           [0017]      FIG. 3  is a side view of a seat according to an embodiment of this invention; 
           [0018]      FIGS. 4   a - 4   e  are side views of a seat according to an embodiment of this invention in different swivel positions; 
           [0019]      FIGS. 5   a  and  5   b  are a side view and a perspective view, respectively, of a seat according to an embodiment of this invention in different swivel positions; 
           [0020]      FIG. 6   a  is a perspective view of a motor vehicle seating arrangement according to an embodiment of this invention; 
           [0021]      FIG. 6   b  is a partial perspective view of a seat belt according to an embodiment of this invention; 
           [0022]      FIGS. 7   a - 7   d  are side views of a seat according to an embodiment of this invention. 
       
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0023]    Exemplary embodiments of the invention are shown in the drawings and explained in greater detail in the following description. 
         [0024]    In the figures the same reference symbols denote the same or functionally the same components. 
         [0025]    In  FIG. 1  reference symbol  1  denotes a floor carpet in a passenger compartment of a motor vehicle. The passenger compartment ends at a cargo compartment at platform  5 . Parallel first and second rails  10   a,    10   b  are attached to floor carpet  1 . Displaceably mounted passenger seats  15   a,    15   b  and  15   d,    15   e  are provided in rails  10   a,    10   b,  respectively. Passenger seats  15   a,    15   d  are located in a first front seat row R 1 , and passenger seats  15   b,    15   e  are located in a middle seat row R 2 . Two emergency seats  15   c,    15   f  are fitted in a receiving device (to be explained later) in a rear seat row R 3 , which lies immediately in front of the cargo compartment. Emergency seats  15   c,    15   f  are not displaceable. Reference symbols SP 1 , SP 2 , SP 3  denote persons who are sitting on passenger seats  15   d,    15   e,    15   f,  respectively. 
         [0026]    With reference to passenger seat  15   a,  some features which are also present in passenger seats  15   b,    15   d,    15   e  are explained in greater detail below, but for reasons of clarity these features are not denoted separately with reference symbols. 
         [0027]    Passenger seat  15   a  has an outer seat shell  151  of plastic, in which an inner seat cushion device  152  is fitted. A headrest  153  is provided retractably in seat cushion device  152  in the head region. Reference symbol  154  denotes an additional headrest which is retracted in the seat cushion device  152  at the longitudinal end of the seat region of seat cushion device  152 . 
         [0028]    Reference symbols  155 ,  156 ,  157  each denote a seat belt lock whose functions are explained in more detail later. Finally, reference symbol  158  denotes a cover for a bearing device by means of which passenger seat  15   a  is mounted retractably in rail  10   a.    
         [0029]      FIG. 2   a  shows rail  10   a  without a passenger seat inserted, whereas  FIG. 2   b  shows how passenger seat  15   a  is inserted into rail  10   a  by means of a further rail  12   a.  It should be noted that rail  10   a  is illustrated in  FIG. 1  such that runs continuously along the floor  1 . This may stabilize the vehicle by increasing the rigidity of the floor  1 , but other rails  10   a  are within the scope of the invention. For example, two shorter rails  10   a,  one for each seat  15   a,    15   b,  may be provided. 
         [0030]    As shown in  FIG. 2   a,  rail  10   a  has an essentially U-shaped cross-section. Support devices  105   a,    105   b,  on each of which is mounted a flap  110   a,    110   b,  are provided on the upper sides of the each of the flanks of rail  10   a.  The flaps  110   a,    110   b  run essentially parallel to the base of rail  10   a  in the condition without the passenger seat inserted ( FIG. 2   a ). 
         [0031]    Reference symbol  50  denotes a floor panel of the motor vehicle, into which rail  10   a  is inserted such that support devices  105   a,    105   b  rest on floor panel  50 . 
         [0032]    Floor carpet  1 , for example a plastic mat, has a gap  100  running longitudinally along the rail center, which gap is kept essentially closed by a magnet device  101  in the condition without the inserted passenger seat, so that floor does not curve. 
         [0033]    As shown in  FIG. 2   b,  the bearing device which supports the passenger seat in the motor vehicle has a second rail  12   a  which is inserted in first rail  10   a  so that it can be slid in the longitudinal direction. Roller bearings  11   a,    11   b  are inserted between first rail  10   a  and second rail  12   a  to minimize friction. First and second supporting struts  159   a,    159   b  ( FIG. 3 ) are fitted on a horizontal swivel axis  160   a,  which is pivoted in second rail  12   a.  Struts  159   a,    159   b  are connected to seat shell  151 . When the seat  15   a  is inserted, supporting struts  159   a,    159   b  force flaps  110   a,    110   b  and floor  1  outwardly upwards in the region of rail  12   a.    
         [0034]      FIG. 3  illustrates the seat position P 1  shown in  FIG. 1 , oriented in the forward-facing direction, with the struts  159   a,    159   b  in a first angular position angled to the rear (to the right in  FIG. 3 ). First and second supporting struts  159   a,    159   b  run along swivel axes within seat shell  151  similar to those explained in relation to second rail  12   a.  The two supporting struts  159   a,    159   b  thus assume the form of a four bar linkage. 
         [0035]    In seat position P 1  shown in  FIG. 3 , a stop (not shown) provided in the seat shell and in inner rail  12   a  prevents supporting struts  159   a,    159   b  from being able to yield further to buckling in the backward direction. A change of angle in the forward direction is effected by a self-locking of a drive motor (not shown) installed preferably in passenger seat  15   a.  The motor swivels seat shell  151 , and hence the entire passenger seat  15   a,  from seat position P 1  to a seat position P 5  oriented in the backward-facing direction, which is explained in detail below with reference to  FIGS. 4   a  to  e.    
         [0036]    It should now be mentioned that seat shell  151  is shaped symmetrically about an axis of symmetry MA, and is divided into first and second half-shell regions HS 1 , HS 2 . Each half-shell region HS 1 , HS 2  can serve either as a backrest region or as a seat region. 
         [0037]    Turning now to  FIGS. 4   a - e,    FIG. 4   a  corresponds to seat position P 1 , already explained with reference to  FIG. 3 . When the drive motor (not shown) is actuated, the angular position of supporting struts  159   a,    159   b  changes. 
         [0038]      FIG. 4   b  shows an intermediate position P 2 , from which it can be seen that seat cushion device  152  is movable relative to seat shell  151 , and that headrests  153 ,  154  can be adjusted relative to seat cushion device  152 . The latter takes place by means of corresponding further drive motors or reduction gears which are coupled to the first drive motor. 
         [0039]    The representation in  FIG. 4   c  shows the achievement of a central position P 3 , where seat shell  151  is tilted such that its axis of symmetry MA is perpendicular to rail  10   a.  In this position, headrest  153  is further retracted in seat cushion device  152  and headrest  154  is further extended from seat cushion device  152 , compared to position P 2 . Moreover, seat cushion device  152  is further to the left side of seat shell  151 . 
         [0040]    An intermediate position P 4 , which is a mirror image of seat position P 2 , is shown in  FIG. 4   d.  Supporting struts  159   a,    159   b  are now being angled forward. 
         [0041]    Finally, with reference to  FIG. 4   e,  seat position P 5 , which is oriented in the backward-facing direction, is reached. In this seat position P 5  the backrest region and the seat region have been swapped in comparison to seat position P 1 . 
         [0042]    Furthermore, headrest  153  is fully retracted and headrest  154  is fully extended in seat position P 5 . Moreover, seat cushion device  152  lies essentially flush with seat shell  151  in the new seat region in the longitudinal direction (bottom right in the Figure), whereas seat cushion device  152  projects from seat shell  151  in the new backrest region (top left). 
         [0043]    Similar to seat position P 1 , a stop (not shown) is provided in seat shell  151  and in rail  12   a  for supporting struts  159   a,    159   b,  which stop prevents supporting struts  159   a,    159   b  from buckling further in the forward direction. Backward buckling in the backward direction, for example due to vibration, is prevented by the self-locking of the drive motor (not shown). 
         [0044]    It should be mentioned that unintentional actuation of the swivel mechanism of passenger seat  15   a,    15   b,    15   d  or  15   e  can be prevented by providing a detector, such as a weight sensor, which deactivates the drive motor as long as the passenger seat concerned is occupied. 
         [0045]    It should also be mentioned that the displacement of seat cushion device  152  relative to seat shell  151  is in this example can be achieved by means of suitable rails (not shown) between seat shell  151  and seat cushion device  152 . 
         [0046]    A backrest adjustment mechanism will now be described with reference to  FIGS. 5   a,    5   b.  An air cushion pad  170  is provided between seat shell  151  and seat cushion device  152 . The pad  170  enables a distance between seat shell  151  and seat cushion device  152  to be changed in the region of air cushion pad  170 . In seat position P 1  shown in  FIGS. 5   a,    5   b,  this effects a displacement of seat cushion  152  in forward direction C and backward direction C′, thereby providing a user-specific adjustment. 
         [0047]    Another air cushion pad  170  is provided in the other half shell. More air cushion pads may be provided in further locations between seat shell  151  and seat cushion device  152 , thereby effecting a fine adjustment to the contours of the sitting person. 
         [0048]    Air cushion pad  170  can be actuated by means of a suitable air compressor (not shown). 
         [0049]    A seat belt mechanism will now be described with reference to  FIGS. 6   a,    6   b.  In the pelvic region of seat shell  151 , on the left side of seat  15   a  is a safety reel device  161 , with a reelable seat belt  80 . On the right side is a first seat belt lock  156 . A second seat belt lock  155  is provided at the longitudinal end of first half-shell region HS 1 , and a third seat belt lock  157  is provided at the longitudinal end of second half-shell region HS 2 , on the left side of seat shell  151 . Seat belt locks  155 ,  156 ,  157  and seat belt reel device  161  are integral to seat shell  151 . 
         [0050]    With reference to  FIG. 6   b,  two stop tongue parts  81   a,    81   b  are provided one behind the other on one belt end  82  of seat belt  80  projecting from seat belt reel device  161 . In seat position P 1  shown in  FIG. 6   a,  seat belt  80  is first reeled completely in seat belt reel device  161 , only belt end  82  and the two stop tongue parts  81   a,    81   b  projecting from it. 
         [0051]    For fastening the belt in seat position P 1 , the user first locks stop tongue part  81   a  in seat belt lock  156 , then stop tongue part  81   b  in seat belt lock  157 . This therefore provides the normal three-point fastening. To release the belt the user merely releases seat belt lock  156 , seat belt lock  157  remaining locked as long as seat position P 1  is maintained. 
         [0052]    If a change in position is attained by swiveling from seat position P 1  to seat position P 5 , both seat belt locks  156  and  157  are released, and the belt is again reeled completely in seat belt reel device  161 . 
         [0053]    When seat position P 5  is reached, stop tongue part  81   a  is again locked in seat belt lock  156 , but in this seat position stop tongue part  81   b  is locked in seat belt lock  155 . 
         [0054]    It should be noted that automatic release of seat belt lock  155  or  157  could be provided in the case of swiveling passenger seat  15   a  from seat position P 1  to seat position P 5 . 
         [0055]    An emergency seat displacement mechanism will now be described with reference to  FIGS. 7   a - 7   d.    FIG. 7   a  shows passenger seat  15   e  in seat position P 1 , i.e. oriented in the forward direction. Reference symbols E 1 , E 2  denote a receiving device provided on the rear side of half-shell HS 2 , e.g. lugs, pockets or hooks, for receiving a corresponding engaging device H 1 , H 2 , e.g. hooks on the lower side of a seat part  172  of emergency seat  15   f,  seat part  172  being connected by a joint  173  to rear part  171  so that it folds. 
         [0056]    Also with regard to  FIG. 7   a,  reference symbols A 1 , A 2 , A 3  each denotes a locking element receiving device connected to the vehicle body (not shown). Stop elements S 1 , S 2 , S 3 , e.g. pins or noses, attached to emergency seat  15   f,  are locked to locking element receiving devices A 1 , A 2 , A 3 , as shown in  FIG. 7   a,  so that emergency seat  15   f  is stably mounted. 
         [0057]    If a user wishes to remove emergency seat  15   f  from platform  5 , to enlarge the cargo space, for example, this can be achieved as follows. 
         [0058]    The user folds seat part  172  of emergency seat  15   f  up, as illustrated by arrow D in  FIG. 7   b.  In this case stop element S 2  is released from locking element receiving device A 3 , as shown in  FIG. 7   b.    
         [0059]    Then, as shown in  FIG. 7   c,  passenger seat  15   e  is moved along rail  10   a  by means of a drive (not shown) in backward direction BR until receiving devices E 1 , E 2  have received engaging devices such as hooks H 1 , H 2  on the lower side of seat part  172  of emergency seat  15   f,  so that they lock. 
         [0060]    In connection with  FIG. 7   c,  this locked position between receiving device E 1 , E 2  and engaging device H 1 , H 2  is shown. Furthermore, receiving devices E 1 , E 2  are vertically adjustable on the rear of seat shell  152  of passenger seat  15   e,  so that the locked emergency seat  15   f  can be raised in direction BH and stop elements S 1 , S 2  can therefore be removed from locking element receiving devices A 1 , A 2  by moving passenger seat  15   e  forward in forward direction BV after leaving the locking position. Emergency seat  15   f  is therefore removed from platform S and the loading space is correspondingly enlarged. 
         [0061]    To re-install emergency seat  15   f  in its receiving devices A 1 , A 2 , A 3 , the steps described above are carried out in reverse. 
         [0062]    While this invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.