(19)

(11)

EP 0 771 139 A1

(12)

(43) Date of publication: 07.05.1997 Bulletin 1997/19 (21) Application number: 95924463.0 (22) Date of filing: 11.07.1995

(51) International Patent Classification (IPC):  A01C 7/ 04( . ) (86) International application number: PCT/GB1995/001647 (87) International publication number: WO 1996/002123 (01.02.1996 Gazette 1996/06)

(84) Designated Contracting States: DE ES FR GB IT (30) Priority: 14.07.1994 GB 19940014211 (71) Applicant: STANHAY WEBB LIMITED Newmarket, Suffolk CB8 7HD (GB)	(72) Inventor: WILLIS, Robert Anthony Peterborough, Cambridgeshire PE8 4HE (GB) (74) Representative: Archer, Philip Bruce, et al  Urquhart-Dykes & Lord European Patent Attorneys New Priestgate House 57 Priestgate Peterborough Cambridgeshire PE1 1JX Peterborough Cambridgeshire PE1 1JX (GB)