Method and apparatus for making a thin, torsional rigidity, metal strip

摘要

A method and apparatus for forming a metal strip into a shape having a transverse concave, convex bow, for example, for forming slats for venetian blinds. The strip material is fed into the nip of a pair of forming rolls having complementary concave and convex peripheral surfaces, to provide the bow. In order to ensure that the resulting bowed strip is formed without any twist, the strip is fed along a substantially straight path upstream of the forming rolls, and the direction of this straight path is adjustable in a plane passing through the nip and parallel to the axes of the forming rolls.