Patent ID: 8650923

Claim:
A method for forming from a plane strip of metal ( 50 ) and for either curving or twisting, or both, a profile ( 50 ) with a cross-section that varies along its length, characterised in that sides ( 77 , 78 ) are folded up on the metal strip in a number of roll-forming units ( 17 , 18 ; 21 , 22 ) to form the profile, wherein the roll-forming units are displaceable sideways and rotated independently of each other, and the sides of the profile formed are rolled vertically in roller pairs ( 82 , 84 ; 83 , 85 ) to become thinner at one of their edges such that the profile is curved or twisted, and in that the roller pairs for thinning the sides of the profile and the sideways displacement and angular motion of the roll-forming units are controlled by the same computer program such that the roller pairs follow the sides vertically and a line (II) between the axles of the rollers in one roller pair is always maintained perpendicular to the side being rolled.