(19)

(11)

EP 0 081 497 A1

(12)

(43) Date of publication: 22.06.1983 Bulletin 1983/25 (21) Application number: 82901070.0 (22) Date of filing: 19.02.1982

(51) International Patent Classification (IPC):  B21D 39/ 02( . ) (86) International application number: PCT/US1982/000211 (87) International publication number: WO 1982/004002 (25.11.1982 Gazette 1982/28)

(84) Designated Contracting States: AT BE CH DE FR GB LI LU NL SE (30) Priority: 11.05.1981 US 19810262216 (71) Applicant: KNUDSON, Gary Art Golden, CO 80401 (US)	(72) Inventor: KNUDSON, Gary Art Golden, CO 80401 (US)