Patent ID: 6715329
Filing Date: 2004-04-06
Classification: B21D

Abstract:
A method of forming a corner region bounded on three sides from a flat plate having side edges having longitudinal extensions, comprising the steps of(a) folding down the side edges of the flat plate by a predetermined height from the plane of the flat plate and across at least a major part of the longitudinal extensions to form side walls in the corner region in a three-dimensional curved transition region, (b) clamping the transition region between a tool having a predeterminable, three-dimensional external shape, of the corner to be formed and a height-adjustable clamping plate pressed against the flat plate, (1) the external shape of the tool being comprised of shaping surfaces having a height same as or slightly larger than a height of the side walls plus a height of an excess projection in the corner region and to be trimmed, the clamping plate having front edges cooperating with the shaping surfaces of the tool forming the corner region, (2) Positioning the front edges flush with the shaping surfaces of the tool or protecting therefrom by a distance slightly smaller than the thickness of the side walls, (c) shaping the transition region by means of at least one roller system overlapping the corner region between the side walls by pressing in the curved transition region against the tool.