Vehicle seat presenting a back that can be folded down fowards

Abstract

A vehicle seat comprising a back and a seat proper secured to a first rigid frame, the first frame being itself supported on both sides of the seat proper by a second rigid frame on which the back is pivotally mounted. The first frame is movable between a first position and a second position relative to the second frame. The first frame is connected to the second frame via at least one link. A locking device is adapted to block the first frame in the first position, and a linking mechanism is adapted to release the locking device while the back is being tilted down towards the seat proper.

1 . A Vehicle seat comprising: 
 a back and a seat proper comprising a cushion secured to a first rigid frame, the first frame being itself supported on both sides of the seat proper by a second rigid frame, the first frame being movable between a first position and a second position relative to the second frame; and    the first frame incorporating a front portion and a rear portion, each connected to the second frame by means of at least one link, the link presenting firstly a bottom portion pivotally mounted on the second frame and secondly a top portion pivotally mounted on the first frame and movable relative to the second frame from an initial position, corresponding to the first position of the first frame, to a retracted position corresponding to the second position of the first frame, the link being designed so that the second position of the first frame is lower than the first position;    the seat being characterized:    in that the back is pivotally mounted directly on the second frame;    in that a locking device is adapted to block the first frame in the first position; and    in that a linking mechanism is adapted to release the locking device while the back is being tilted down towards the seat proper.    
   
   
       2 . A vehicle seat according to  claim 1 , in which the first frame is a sheet metal bucket.  
   
   
       3 . A vehicle seat according to  claim 1 , in which the second frame comprises two cheekplates that surround the bucket.  
   
   
       4 . A vehicle seat according to  claim 1 , in which the locking device comprises at least one blocking member pivotally mounted on the first frame to pivot between a blocking position in which it holds one of the links in its initial position and a release position in which it enables the link to move, the blocking member presenting a cam surface on which the link slides, moving the member towards its release position while the first frame is being moved towards the first position.  
   
   
       5 . A vehicle seat according to  claim 1 , including a spring that urges the link towards its retracted position.  
   
   
       6 . A vehicle seat according to  claim 1 , in which the seat proper is supported by two front legs and two rear legs and in which each second frame is mounted on a front leg in such a way that it pivots.  
   
   
       7 . A vehicle seat according to  claim 1 , in which the second position is further forwards than the first position.  
   
   
       8 . A vehicle seat according to  claim 1 , in which the seat back can be folded down onto the seat proper in a substantially horizontal stool position and in which the release of the locking device is achieved when the back is close to this stool position.  
   
   
       9 . A vehicle seat according to  claim 1 , in which the linking mechanism is a cable that extends between the back and the locking device.