(19)

(11)

EP 0 231 186 A1

(12)

(43) Date of publication: 12.08.1987 Bulletin 1987/33 (21) Application number: 85905247.0 (22) Date of filing: 18.10.1985

(51) International Patent Classification (IPC):  E21C 37/ 10( . ) (86) International application number: PCT/SE1985/000402 (87) International publication number: WO 1986/002404 (24.04.1986 Gazette 1986/09)

(84) Designated Contracting States: DE FR GB IT (30) Priority: 18.10.1984 SE 19840005218 (71) Applicant: Gislaved Aktiebolag S-332 00 Gislaved (SE)	(72) Inventor: DERMAN, Karl, Gustaf S-433 61 Partille (SE) (74) Representative: Linde, Leif  Vernamo Patentbyra AB, Persegard S-274 00 Skurup S-274 00 Skurup (SE)