Abstract: A light alloy seat back frame for a vehicle seat, including a pair of spaced apart side sections, an upper section interconnecting the side sections, a lower section formed into a substantially plate-shape having a width, the lower section extending between lower regions of rear sides of the side sections and interconnecting the side sections, the upper, side and lower sections being integrally made of light alloy, and a belt-shaped metal plate fixed onto a surface of the lower section. The seat back frame further includes a recliner mechanism for allowing a seat back of the vehicle seat to be pivoted with respect to a seat cushion of the vehicle seat. The recliner mechanism comprises cam devices mounted onto lower regions of outer surfaces of the side sections, and an actuating shaft extending along the lower section and interconnecting the cam devices. A metal pipe member for reinforcing a lower part of the seat back frame is mounted around an axial portion of the actuating shaft.

Abstract: A light alloy seat back frame for a vehicle seat, including a pair of spaced apart side sections, an upper section interconnecting the side sections, a lower section formed into a substantially plate-shape having a width, the lower section extending between lower regions of rear sides of the side sections and interconnecting the side sections, the upper, side and lower sections being integrally made of light alloy, and a belt-shaped metal plate fixed onto a surface of the lower section. The seat back frame further includes a recliner mechanism for allowing a seat back of the vehicle seat to be pivoted with respect to a seat cushion of the vehicle seat. The recliner mechanism comprises cam devices mounted onto lower regions of outer surfaces of the side sections, and an actuating shaft extending along the lower section and interconnecting the cam devices. A metal pipe member for reinforcing a lower part of the seat back frame is mounted around an axial portion of the actuating shaft.