Patent ID: 6044680
Filing Date: 2000-04-04
Classification: B21C

Abstract:
A process of machining a sheet without removal of material, comprising:nipping said sheet between two longitudinal tool bearings engaging the sheet across a section of the latter, said bearings delimiting between them a calibration opening, whose large dimension is greater than the width of the sheet to be machined and whose small dimension determines the thickness of the sheet along said section;grasping said sheet at one end, over the whole width of said sheet, adjacent the calibration opening;pulling the sheet by said end so as to advance an initial section of the sheet from within the plane containing the calibration opening and thus pass the sheet through the calibration opening, while said longitudinal bearings are kept supported against said sheet, and progressively changing the spacing between the bearings as the sheet passes through the calibration opening so as to control said thickness of the sheet that has passed through the calibration opening according to a predetermined relationship as a function of the distance that the initial section has been advanced beyond the calibration opening, said predetermined relationship being such that the thickness of the sheet is caused to be continuously changed along the length between the initial section and the calibration opening.