Patent ID: 6269672
Filing Date: 2001-08-07
Classification: B21D,Y10T

Abstract:
A method of controlling the curling operation of two metal blank workpieces to form a hinge comprising:providing a first metal blank workpiece cut to a predetermined shape of a hinge receiver blank and having a portion with an inside surface adapted to be curled;indenting the inside surface of the first blank portion for curling with parallel grooves by a predetermined indenting procedure selected from the group consisting of punching, cutting and filing;providing a second metal blank workpiece having an axis portion;curling the axis portion; andcurling the indented blank portion of the first metal blank workpiece by one of a curling device or a roll forming device substantially 360.degree. over the curled axis portion of said axis portion containing blank workpiece;whereby the curled portion of the first metal blank workpiece is smoothly formed without cracks or irregular deformation to form said hinge.