Patent ID: 7310878

Claim:
A method for manufacturing a lower body component for a vehicle, the method comprising: forming a one-piece floor pan at least partially defining a vehicle passenger compartment; wherein said floor pan substantially extends longitudinally at least the entire length of the at least partially defined vehicle passenger compartment; forming a one-piece reinforcement structural member; and reinforcing said one-piece floor pan with said one-piece reinforcement structural member; simultaneously forming said one-piece floor pan and said one-piece reinforcement structural member with a pair of weldable sheet metal blanks using movable profile forming dies, including stacking said pair of weldable sheet metal blanks between said movable profile forming dies sufficiently closely together to define a common interface therebetween; heating said movable profile forming dies so that the temperature of said stacked weldable blanks reaches a temperature sufficient for superplastic forming; closing said profile forming dies on said stacked weldable blanks to establish a sufficient seal at said common interface to partially define an internal chamber between said stacked weldable blanks and a plurality of separate perimeter pressurization chambers inside said forming dies each positioned outside of said common interface; and supplying pressurized gas into said internal chamber and said plurality of separate perimeter pressurization chambers to increase the volume of said internal chamber and said plurality of separate perimeter pressurization chambers to simultaneously effect the stretching of said weldable blanks into said profiling dies and to thereby plastically deform said stacked weldable blanks into a lower body component and a one piece reinforcement structural member each having the profile of a different one of said profile forming dies.