Abstract:
A seat assembly for a motor vehicle includes a central support element, fixed essentially vertically in a vehicle cabin to which the seats are fitted. The seat assembly includes connector bodies arranged at one end of the support element for fixing to a part of the cabin, the connector bodies permitting a displacement of the assembly along a longitudinal axis of the vehicle.

Description:
BACKGROUND OF THE INVENTION 
   I. Field of the Invention 
   The present invention relates to a seat assembly for a motor vehicle, as well as a motor vehicle fitted with such a seat assembly. 
   II. Description of Related Art 
   Motor vehicle seats, and in particular the front seats, must meet a number of requirements, in particular safety, comfort, and durability requirements. 
   To meet these requirements, such seats have become relatively voluminous. In fact, they have a heavy and bulky frame and hinges to withstand violent impacts caused when the motor vehicle strikes an obstacle or when the vehicle overturns. Although the presence of such voluminous frames and hinges increases the overall bulk of the seat, the rigidity of the seat remains inadequate. 
   There are solutions that consist in relocating the central mountings placed under the seat to side mountings under the seat, which make it possible to increase the space available for the feet of the rear passengers in the vehicle, but which do not improve the space available at the level of the knees of the rear passengers in the vehicle. 
   The document EP 1,247,724 describes a seat comprising an additional mounting point, which improves the strength in the event of an impact of the vehicle, and reduces the bulk of such a seat. However, the number of parts required for the construction of this seat is large, and therefore costly. 
   The document WO 03/057524 relates to a pair of front seats of a motor vehicle comprising a central pillar extending from the floor to the roof of the vehicle and a central support forward of the central pillar. The seat cushion, the squab, and the headrest of the two seats are connected to the central pillar by support members. Such a pair of seats does not allow any adjustment of the position of the seats, which is a real nuisance and very uncomfortable for the passengers of a motor vehicle. 
   BRIEF SUMMARY OF THE INVENTION 
   The subject of the present invention is a seat assembly for a motor vehicle, with adjustable positioning, and having a light and thin frame making it possible to limit the bulk of the vehicle while improving the rigidity and the strength of the seats, at low cost. 
   Therefore, according to one aspect of the invention, a seat assembly for a motor vehicle is provided, comprising a central supporting element intended to be mounted generally vertically in the passenger compartment of the vehicle, and on which said seats are mounted. The assembly comprises connecting members, disposed at one end of said supporting element and intended to be mounted on a portion of the passenger compartment. Said connecting members are able to permit a longitudinal movement of said assembly. 
   Such a seat assembly consequently has a light and thin frame limiting the bulk of the vehicle, while improving the rigidity and the strength of the seat, at low cost. Moreover, such an assembly allows an adjustment of the positioning of the seats. 
   In a preferred embodiment, at least one of the seats comprises side connecting members, disposed between said seat and said supporting element, and able to permit a longitudinal translational movement of said seat in relation to said supporting element. 
   It is then possible to adjust the positioning of a seat independently of the positioning of the other seats. It is in fact important that each person be able to adjust the positioning of his seat independently of the others. 
   Advantageously, at least one of the seats is mounted permanently on said supporting element. 
   The movement of the supporting element allows the adjustment of the positioning of at least one permanently mounted seat, which reduces the cost, by keeping the number of connecting members to a minimum. 
   In a preferred embodiment, at least one of the seats comprises first lower connecting members intended to connect the seat cushion of said seat to a lower portion of the passenger compartment. 
   These seats comprise two mounting points for attachment to the passenger compartment, which improves the rigidity and the strength of the seat. 
   In a preferred embodiment, said connecting members comprise upper connecting members, disposed at an upper end of said supporting element, and intended to be mounted on an upper portion of the passenger compartment, said upper connecting members being able to permit a movement of said assembly along a longitudinal axis of the vehicle. 
   In an advantageous embodiment, said connecting members moreover comprise lower connecting members, disposed at a lower end of said supporting element, and intended to be mounted on a lower portion of the passenger compartment, said lower connecting members being able to permit a movement of said assembly along a longitudinal axis of the vehicle. 
   A longitudinal translation of the assembly is then guided so as to reinforce the generally vertical support of the supporting element. The rigidity of the passenger compartment is then improved, because of an additional connection between the supporting element and the passenger compartment. 
   Moreover, at least one seat comprises a device for adjusting the vertical position of the movable seat cushion of said seat. 
   This seat can then be raised or lowered according to the shape and size of its occupant. 
   In a preferred embodiment, the assembly comprises at least one safety belt disposed on said supporting element. 
   According to another aspect of the invention, it provides a motor vehicle fitted with a seat assembly such as previously described. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention and its advantages will be better understood from a study of the detailed description of embodiments taken as non-limiting examples, and illustrated by figures, in which: 
       FIG. 1  illustrates a rear view of the seat assembly, according to  FIG. 2 , in a first embodiment; 
       FIG. 2  illustrates a schematic longitudinal section view of a seat assembly according to one aspect of the invention; and 
       FIG. 3  illustrates a rear view of the seat assembly, according to  FIG. 2 , in a second embodiment. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Illustrated in  FIG. 1  is a seat assembly  1  according to one aspect of the invention, comprising two seats intended to be mounted in the front of a motor vehicle, even in the center of a large-size vehicle.  FIG. 2  is a cross-section view of the left-hand front seat, along the lines II-II of  FIG. 1 , the whole being numbered  2 , taken here as a reference seat. 
   The seat assembly  1  comprises a central supporting element  3  intended to be mounted generally vertically in the passenger compartment of the vehicle, on which are mounted the seats. The supporting element  3  comprises upper connecting members, disposed at an upper end of the supporting element  3 , and intended to be mounted on an upper portion of the passenger compartment illustrated schematically by a fixed point  4 . 
   It will be noted, however, that the invention also applies to a supporting element  3 , usually comprising connecting members intended to be mounted on a portion, for example a lower portion, of the passenger compartment. 
   In the rest of the description, it will be assumed that the connecting members are upper connecting members. 
   The upper connecting members are provided in the form of an upper runner  5  and an upper slider  6  connected to the supporting element  3  and able to slide on the upper runner  5  connected to an upper portion  4  of the passenger compartment. The upper slider  6  can be moved longitudinally forward or backward in relation to the upper portion  4  of the passenger compartment. Of course, the slider  6  is able to be locked in position on the upper runner  5  or unlocked. 
   The seat  2  is here mounted on the supporting element  3  by means of an extension arm  9   ext  of the seat cushion  9  of the left-hand front seat  2 . 
   The left-hand front seat  2  comprises a frame including a movable seat cushion portion  9   m  extending generally horizontally while being slightly inclined toward the rear, and a squab portion or backrest portion  10  extending generally vertically while being generally inclined toward the rear. The movable seat cushion portion  9   m  and the squab portion  10  are respectively covered with padding or trim  9   a  and  10   a.    
   The seat cushion portion  9  of the frame comprises a central mounting or base  11 . The base  11  has an upper end fixed to the seat cushion portion  9  and a lower end fixed to first lower connecting members intended to connect the seat cushion portion  9  of the seat  2  to a lower portion of the passenger compartment illustrated schematically by a fixed point  12 . 
   The first lower connecting members of the left-hand front seat  2  are provided in the form of a first lower runner  13  and a first lower slider  14  connected to the seat cushion portion  9  and able to slide on the first lower runner  13  connected to a lower portion  12  of the passenger compartment. The first lower slider  14  can be moved longitudinally forward or backward in relation to the lower portion  12  of the passenger compartment. Of course, the first lower slider  14  can be locked in position on the first lower runner  13  or unlocked. 
   The movable seat cushion portion  9   m  comprises moreover a device for adjusting  15  its vertical position, located under the movable seat cushion  9   m , generally at its center. 
   The squab portion  10  and the movable seat cushion portion  9   m  are connected by hinge pins  16 . The upper end of the squab portion  10  comprises a headrest  17 . 
   The assembly  1  also comprises a safety belt  18  disposed on the supporting element  3  and intended for the occupant of the left-hand front seat  2 . The safety belt  18  comprises a retractor  19  installed in a bottom portion of the supporting element  3 , and a strap  20 . The strap  20  coming out of the retractor  19  rises along the supporting element  3  to a guide loop  21  mounted on the supporting element  3  level with the headrest  17 . The strap  20  passes through the guide loop  21  and comprises a buckle  22  at one end away from the retractor  19 . The buckle  22  is held at the end of its travel on the guide loop  21  by the tension exerted by the retractor  19  on the strap  20 . 
   Illustrated in  FIG. 1  is, moreover, a right-hand front seat  23  of the two-seat assembly  1 . In this example of an assembly comprising two seats, the left-hand front seat  2  is connected to the supporting element  3 , or, in others words, is mounted permanently on the supporting element  3 . The right-hand front seat  23 , like the left-hand front seat  2 , is mounted on the supporting element  3  by means of side connecting members disposed between the right-hand front seat  23  and the supporting element  3 , at the level of the seat cushion  26 . The side connecting members are able to permit a longitudinal translational movement of the right-hand front seat  23  in relation to the supporting element  3 . 
   In like manner, the right-hand front seat comprises one movable seat cushion portion  26   m  and one squab portion or backrest portion  27 . The movable seat cushion portion  26   m  and the squab portion  27  are respectively covered with padding or trim. The seat cushion portion  26  of the frame comprises a central mounting or base  28 . The base  28  has a lower end fixed to first lower connecting members intended to connect the seat cushion  26  of the seat  23  to a lower portion of the passenger compartment illustrated schematically by a fixed point  29 . 
   The first lower connecting members of the right-hand front seat  23  are also provided in the form of a first lower runner  30  and a first lower slider  31  connected to the seat cushion portion  26  and able to slide on the first lower runner  30  connected to a lower portion  29  of the passenger compartment. The movable seat cushion portion  26   m  comprises moreover a device for adjusting  32  its vertical position. 
   The squab portion  27  and the movable seat cushion portion  26   m  are connected by hinge pins  33 . The upper end of the squab portion  27  comprises a headrest  34 . 
   The assembly  1  also comprises a safety belt  35  disposed on the supporting element  3  and intended for the occupant of the seat  23 . The safety belt  35  comprises, like the belt  18 , a retractor  36 , a strap  37 , a guide loop  38 , and a buckle  39 . 
   Of course, the connections which are able to allow a movement of one element in relation to another can be locked in position or unlocked. 
   The left-hand front seat  2  is mounted permanently on the supporting element  3 , while the right-hand front seat  23  comprises side connecting members, disposed between the right-hand front seat  23  and the supporting element  3 , and able to permit a longitudinal translational movement of the right-hand front seat  23  in relation to said supporting element  3 . 
   The side connecting members which connect the right-hand front seat  23  with the supporting element  3  are also provided in the form of a runner  40 , and a slider  41  connected to the seat cushion portion  26  and able to slide on the runner  40 . 
   It is then possible to adjust independently the positioning of the left-hand front seat  2  and right-hand front seat  23 . In a variant, the right-hand front seat  23  can be connected to the supporting element  3 , and the left-hand front seat  2  can be moved by longitudinal translation in relation to the supporting element  3 . 
   Moreover, the supporting element  3  comprises second lower connecting members, disposed at a lower end of the supporting element  3 , and intended to be mounted on a lower portion of the passenger compartment illustrated schematically by a fixed point  42 , by means of a peg  43 . The lower connecting members of the supporting element  3  are able to permit a movement of said assembly  1  along the longitudinal axis of the vehicle. 
   The lower connecting members of the supporting element  3  are also provided in the form of a runner  44 , and a slider  45  connected to the seat cushion portion  9  and able to slide on the runner  44 . 
   The peg  43  prevents translation of an interface  46  between the runners  40  and  44 . 
   The fixed point  42  to which the peg  43  is connected, is here part of a tunnel  47 . 
     FIG. 3  illustrates a variant, in which the runners  40  and  44 , as well as the associated sliders  41  and  45 , are directly fixed to the fixed point  42 , without the presence of a peg  43 , nor is there an interface  46  between the runners  40  and  44 . 
   The invention makes it possible to reduce the bulk of a motor vehicle, and increase the rigidity of the seats in the event of an impact, all at low cost. 
   The invention makes it possible to conserve the usable space in a passenger compartment of a motor vehicle, in particular for rear passengers. The seat can be used to strengthen the whole structure of the motor vehicle.