Abstract: A vehicle seat assembly having a seat back which pivots during a rear impact vehicle collision in Such a manner that the upper end of the seat back rotates foreword. The pivoting seat back includes a releasable latch mechanism to hold the seat back frame fixed in a predetermined position about a pivot axis. The latch mechanism is releasable by inertia forces in response to a rear vehicle collision, to release the latch member and free the seat back frame for rotation about the pivot axis.

Abstract: A back frame for a vehicle seat assembly having an upright frame member capable of supporting compressive and tensile loading and a secondary, tensile load carrying member capable only of supporting significant loads in tension. The tensile load carrying member is attached to the upright frame member at the upper end of the back frame and extends downward behind the upright frame member and is attached to a base at the lower end of the back frame. The upright frame member is also attached to the base at the lower end of the back frame. The result is a triangular truss formed by the upright frame member, the tensile load carrying member and the base.