Abstract: A sitting section of a vehicle seat which provides comfort for an occupant of the seat and affords protection against the occupant sliding forwards in the event of a crash, the sitting section having a frame with a seat shell having a selected natural vibration and a forward arched section and a section rearward of the arched section which is adapted to oscillate freely and is reinforced with corrugations, the seat shell sloping downwards towards the rear at an angle of about 15.degree., and the seat shell having relatively thin upholstery fitted thereover.

Abstract: A vehicle seat back frame including two bracing members, one being linearly extended from the lower end of the outboard upright member to the upper end of the inboard upright member and the other being extended linearly from the lower end of the inboard upright member to the upper end of the outboard upright member, the bracing members being connected together at a point intermediate their ends so that a side impact load applied to the seat back frame will place one of the bracing members fully, and the upper half of the other member, in tension substantially instantaneously upon the application of the load to the seat back frame, enabling the seat back frame to resist lateral deformation due to side impact forces applied to the seat back frame.