Patent ID: 8197740

Claim:
A method of molding a sheet-form raw material blank to form a molded product, said method comprising the steps: a) actively driving first and second outer edge molds toward one another relative to a stationary machine frame, which comprises actuating at least one first piston-cylinder device connected between one of said outer edge molds and said stationary machine frame, and thereby contacting, pressing and slippingly holding an edge rim of said raw material blank between said first and second outer edge molds, so as to support said raw material blank at a first tension yet allow slipping thereof at a second tension higher than said first tension arising for said support, further comprising establishing a holding pressure applied by said first and second outer edge molds onto said edge rim of said raw material blank so as to allow said slipping, by positively stopping a closing motion of said first and second outer edge molds with mechanical stop members to positively achieve and enforce a predefined spacing between said first and second outer edge molds; b) beginning after a beginning of said step a), actively driving first and second inner core molds toward one another relative to said first and second outer edge molds, which comprises actuating at least one second piston-cylinder device connected between one of said inner core molds and one of said outer edge molds, and thereby contacting, deforming and molding a main central body portion of said raw material blank between said first and second inner core molds so as to form a molded central body portion of said molded product; c) during said step b), continuing said slipping of said raw material blank between said first and second outer edge molds toward said first and second inner core molds, and molding said edge rim of said raw material blank between said first and second outer edge molds to form a molded edge rim of said molded product; and d) permanently retaining said molded edge rim as a permanent part of said molded product.