Patent ID: 6907763
Filing Date: 2005-06-21
Classification: B21D,Y10T

Abstract:
1. A method for hemming two aluminum sheet metal panels together wherein one panel has a generally perpendicular flange with a width L from a bend line on said one panel and to a free edge of said one panel, comprising the steps of: positioning an outer edge of the other panel adjacent said bend line; bending said flange so that said flange overlies the outer edge of said other panel; and thereafter compressing said flange against an outer peripheral portion of said other panel so that said outer peripheral portion of said other panel is sandwiched in between said flange and said one panel; wherein said bending step further comprises the step of impacting a curvilinear prehemming tool against an outer edge of said flange, said prehemming tool has a curvilinear surface with a radius R wherein said generally perpendicular flange has an outer bending radius R in the range of (1.0 mm+t)>R>(0.2 mm+t), where t=thickness of said one of said panels in millimeters.