Automobile vehicle seat, has framework coupled to support structure by primary and secondary connections that maintain backrest in usage position, and enable superior part of backrest to move towards rear until safe position

The seat has a support structure (5) with a rear beam part (7) including a head-support (4). A framework (8) of a backrest is connected to the support structure (5) by primary and secondary connections (10, 14) which are arranged at different heights. The connections normally maintain the backrest in a usage position, and enable a superior part of the backrest to move towards rear until a safe position. The connections enable the superior part of the backrest to move towards rear until a safe position when the backrest subjects to a strong solicitation higher than a predetermined limit, towards rear. Siège de véhicule comprenant une structure de support rigide (5) dotée d'une poutre centrale arrière (7) qui porte un appui-tête (4), une assise (2), et un dossier (3) porté par la poutre centrale (7). Le dossier est monté pivotant sur la poutre centrale par deux liaisons (10 ; 14) qui permettent un déplacement du dossier vers l'arrière, sous un effort supérieur à une valeur limite prédéterminée.