Patent ID: 7793809

Claim:
A backpack frame having a front side and a back side, said backpack frame comprising: generally parallel base and top sections extending transversely across and spaced one from the other along a center line of said backpack frame; side rails connecting said base section to said top section, said side rails being arranged on opposite sides of said center line; and a stabilizing rib interconnecting said side rails, said stabilizing rib extending transversely across said center line at an intermediate location between said base and top sections and having ends projecting laterally outwardly from said side rails, said side rails converging inwardly from said base section towards said center line to join said stabilizing rib, and diverging outwardly from said stabilizing rib and away from said center line to join said top section, the perimeter of said backpack frame being defined by the outermost edges of said bottom and top sections, said side rails and the laterally outwardly projecting ends of said stabilizing rib, and wherein a bottom edge of said top section and bottom and top edges of said stabilizing rib coact at their respective junctures with inner and outer edges of said side rails to define concavities having radii ranging from 25 to 75% of the width of said side rails.