Patent ID: 6675624
Filing Date: 2004-01-13
Classification: B21D

Abstract:
Method for forming a double-curved object by means of stretching a sheet, comprising:a) providing a shaping die with a shaped die surface having a first part and a second part wherein the first part is a single curved section which gradually merges into the second part which is a double curved section; b) positioning the sheet in such a manner that it extends along the shaped die surface of the shaping die; c) clamping two opposite ends of the sheet into in each case one clamping head which extends along the full respective edge; d) during a working stroke, moving the sheet with clamping heads and the shaping die towards one another, in such a manner that the sheet comes into contact with the second part of the die surface and as a result of continued movement of shaping die and clamping jaws, comes into contact with the first part of the die surface; e) influencing at least one clamping of the sheet in such manner that a sheet edge section which is next to the first part of the die surface executes a greater advancing movement compared to a sheet-edge section which is adjacent to the second part of the die surface.