Backrest frame for vehicle seat

摘要

The frame consists of an upper section (7) which is mounted on top of a lower one (6) with two vertical side uprights (8,9). The upper section has a torsion bar (11) which extends horizontally between two ends (11a,11b) connected to the lower section's two uprights and a superstructure (12,14a) which extends above the torsion bar. The superstructure is joined to at least the second end (11b) of the torsion bar, the first end (11a) of which is fixed from rotating relative to the first upright (8) of the lower frame section. The torsion bar's second end (11b) is able to turn freely relative to the second frame upright. The seat's safety belt (5) is connected to a reel mounted on the seat frame superstructure and passes through a slot (14b) in one of its sections (14a). The frame and torsion bar are designed so that the torsion bar takes up the effort applied to the frame superstructure by the seat belt.