METHOD FOR THE ZIGZAG-LIKE FOLDING OF A STRIP-LIKE FOIL

摘要

The method for the zigzag-like folding of a strip-like foil includes the following steps in an advantageous embodiment: 1. prepleating, whereby a zigzag-like or wave-shaped folding is effected in which the folded edges are formed in cross-section as arcs with a radius of curvature greater than about 1 mm; 2. follow-up forming of each second folded edge in that a coining tool is used to influence the fold angle and to reduce the radius of curvature of the folded edge to a value smaller than 1 mm; 3. follow-up forming of the remaining folded edges in the same manner as during the second step. The follow-up forming steps are executed with tumble pressing devices (1, 2) which respectively include a rotatable toothed roll (20) and a coining tool (21). The coining tool is drivable by means of an eccentric device (22) and is connected via a pendulum axle (214a) with a vertically displaceable slider (215). The coining tool, in cooperation with a respective tooth (201) of the roll (20), reduces the radius of curvature of a folded edge and can additionally influence the associated fold angle.