Flexible back pack frame

Claim 1

A flexible, laminated back pack frame conforming to the dual curvature of a wearer's back for supporting and distributing a load over the wearer's back and shoulder region while simultaneously accomodating movement of the wearer by readily deforming to fit the changing contour of the wearer's back in response to both bending and twisting movements of his body, said frame comprising in combination: (a) a pair of parallel, upright laminated members each having an outwardly curved upper section conformingly fitted to the upper portion of the wearer's back and shoulder region, and an inwardly curved lower portion conformingly fitted to the lower position of the wearer's back, said upright members comprising a laminate having a first ply of glass reinforced plastic positioned adjacent the wearer's back, a second ply of glass reinforced plastic and a wooden filler ply situated between and bonded to said glass reinforced plastic plys, said laminate being continuously flexible into a conforming relationship with the wearer's back in response to body movements; (b) upper, central, and lower laminated horizontal crosspieces, each individually bonded to and spanning said upright members, said crosspieces having a curvature conforming to the lateral curvature of the wearer's back at the respective locations of each of said crosspieces; and (c) first and second diagonal brace members extending diagonally between said upright members, said diagonal brace members intersecting at a position adjacent the middle of said second crosspiece and having a curvature conforming to the adjacent curvature of the wearer's back; whereby the back pack frame readily and continuously conforms to the contour of the wearer's back in response to both bending and twisting motions of his body and thereby distributes the load over the wearer's back and shoulder region.