Patent ID: 6210623
Filing Date: 2001-04-03
Classification: B21D,B29C

Abstract:
A blow down method for hydroforming sheet material within a cavity in a platen in conformance with a mold supported upon a table upon juxtapositioning of the platen with the table, said method comprises the steps of:a) supporting the sheet material upon the mold;b) establishing a gaseous pressure environment within the cavity adjacent the sheet material to force conformance of the sheet material with the mold;c) sealing the cavity with a circumscribing seal extending between the platen and the table upon exercise of said step of establishing to maintain the pressure in the cavity; andd) containing the seal between a pair of concentric wall members circumscribing the cavity, which concentric wall members extend downwardly from the platen toward the table, including the step of sealing the wall members against the table or sheet material upon juxtapositioning of the platen with the table to protect the seal by preventing migration of the seal toward and away from the cavity.