(19)

(11)

EP 0 050 641 A1

(12)

(43) Date of publication: 05.05.1982 Bulletin 1982/18 (21) Application number: 81901163.0 (22) Date of filing: 29.04.1981

(51) International Patent Classification (IPC):  G11B 23/ 023( . ) (86) International application number: PCT/NO1981/000013 (87) International publication number: WO 1981/003113 (12.11.1981 Gazette 1981/27)

(84) Designated Contracting States: AT CH DE FR LI NL SE (30) Priority: 02.05.1980 NO 19800001295 (71) Applicant: GULBRANDSEN, Gerry N-1600 Fredrikstad (NO)	(72) Inventor: GULBRANDSEN, Gerry N-1600 Fredrikstad (NO) (74) Representative: Noz, Franciscus Xaverius, Ir., et al  Algemeen Octrooibureau P.O. Box 645 NL-5600 AP Eindhoven NL-5600 AP Eindhoven (NL)