Inventors:
Gunter H. Zittel - San Diego CA
Assignee:
Elmag, Inc. - San Diego CA
International Classification:
B21D 2614
Abstract:
An apparatus for deforming a sheet metal workpiece comprises an inductor for generating a magnetic field, a die comprised of substantially non-conductive material, and a workpiece comprised of substantially conductive material situated such that a current flowing in the inductor creates a magnetic field forcing the workpiece toward the surface of the die. Preferably, a flux transfer member is provided between the inductor and the workpiece to improve forming efficiency. In one preferred embodiment, the workpiece is an aluminum beverage container having a wall thickness of approximately 0. 004 to 0. 008 inches. In this embodiment, the waveform of the inductor current preferably comprises damped oscillations, and the frequency of the oscillations is approximately 20 to 60 kilohertz.
