A CROSSMEMBER OF A TORSION BAR REAR SUSPENSION FOR A MOTOR VEHICLE, AND PROCESS FOR DESIGNING SUCH CROSS MEMBER

A cross member of a torsion bar rear suspension for a motor vehicle extends along a longitudinal axis (21) and has two tubular portions (22), arranged at opposite longitudinal ends, and a central portion (24) provided with a longitudinal slit (26) to have an open cross section; this central portion (24) has a wall (28) that connects the tubular portions (22) in the longitudinal direction and defines an axial cavity (29), open radially towards the outside through the longitudinal slit (26); two wings (34) are connected to said wall (28) by means of respective curved portions (35) to protrude into the cavity (29); the length of the development of the cross section of the cross member at a centreline section plane (P1) is greater than the length of the development of the lateral profile of the tubular portions (22).