US Patent 7264302 Lower body construction

With an excessive impact load generated by a side impact or collision, even in the event that a falling deformation of a pillar connected to a side sill occurs at an initial stage of the side impact, triggering a twisting deformation of the side sill as the side sill is pulled along with the falling deformation of the pillar, the side sill is allowed to maintain a high rigidity against the impact load at a middle stage of the side impact due to a projecting surface of a secondary reinforcement panel being made to be oriented upwards by virtue of the twisting deformation of the side sill.