(19)

(11)

EP 0 478 619 A1

(12)

(43) Date of publication: 08.04.1992 Bulletin 1992/15 (21) Application number: 90909170.0 (22) Date of filing: 07.06.1990

(51) International Patent Classification (IPC):  E02D 7/ 18( . ) E02D 15/ 04( . ) E02D 7/ 26( . ) (86) International application number: PCT/GB1990/000880 (87) International publication number: WO 1990/015904 (27.12.1990 Gazette 1990/29)

(84) Designated Contracting States: AT BE CH DE DK ES FR GB IT LI LU NL SE (30) Priority: 21.06.1989 GB 19890015722 27.06.1989 GB 19890014764 31.08.1989 GB 19890019729 (71) Applicants: Roxbury Limited 28 Irish Town (GI) BULLIVANT, Roger Alfred Burton-on-Trent, Staffordshire DE15 0SS (GB)	(72) Inventor: BULLIVANT, Roger, Alfred Park Manor Staffordshire DE15 0SX (GB) (74) Representative: Campbell, Iain Angus, et al  Swindell & Pearson 48 Friar Gate Derby DE1 1GY Derby DE1 1GY (GB)