(19)

(11)

EP 0 834 159 A1

(12)

(43) Date of publication: 08.04.1998 Bulletin 1998/15 (21) Application number: 96918764.0 (22) Date of filing: 19.06.1996

(51) International Patent Classification (IPC):  G07D 7/ 00( . ) (86) International application number: PCT/GB1996/001469 (87) International publication number: WO 1997/001156 (09.01.1997 Gazette 1997/03)

(84) Designated Contracting States: BE CH DE ES FR GB IT LI NL (30) Priority: 22.06.1995 GB 19950012698 (71) Applicant: THE SECRETARY OF STATE FOR DEFENCE DRA Farnborough, Hampshire GU14 6TD (GB)	(72) Inventor: LEWIS, Keith, Loder Malvern Worcestershire WR14 3PS (GB) (74) Representative: Skelton, Stephen Richard  D/IPR DERA Formalities, Poplar 2a No. 19, MOD(PE) Abbey Wood Bristol BS34 8JH Bristol BS34 8JH (GB)