(19)

(11)

EP 0 020 359 A1

(12)

(43) Date of publication: 07.01.1981 Bulletin 1981/01 (21) Application number: 79900935.0 (22) Date of filing: 09.08.1979

(51) International Patent Classification (IPC):  E02B 15/ 04( . ) E02B 15/ 10( . ) (86) International application number: PCT/SE1979/000168 (87) International publication number: WO 1980/000466 (20.03.1980 Gazette 1980/06)

(84) Designated Contracting States: FR (30) Priority: 14.08.1978 SE 19780008598 (71) Applicant: SANDVIK AKTIEBOLAG S-811 81 Sandviken 1 (SE)	(72) Inventor: FAST, Sven Gunnar S-81100 Sandviken (SE) (74) Representative: Taquist, Lennart, et al  Sandvik AB Patents & Licences Fack S-811 81 Sandviken 1 S-811 81 Sandviken 1 (SE)