(19)

(11)

EP 0 486 599 A1

(12)

(43) Date of publication: 27.05.1992 Bulletin 1992/22 (21) Application number: 90913006.0 (22) Date of filing: 06.08.1990

(51) International Patent Classification (IPC):  F41H 9/ 10( . ) G08B 15/ 00( . ) (86) International application number: PCT/GB1990/001224 (87) International publication number: WO 1991/002338 (21.02.1991 Gazette 1991/05)

(84) Designated Contracting States: AT BE CH DE DK ES FR GB IT LI LU NL SE (30) Priority: 07.08.1989 GB 19890018013 (71) Applicants: JARVIS, Colin Peter George Cheshunt, Herts EN8 9EH (GB) RICHARDS, John London E17 (GB)	(72) Inventors: JARVIS, Colin Peter George Cheshunt, Herts EN8 9EH (GB) RICHARDS, John London E17 (GB) (74) Representative: Frankland, Nigel Howard  FORRESTER & BOEHMERT Franz-Joseph-Strasse 38 D-80801 München D-80801 München (DE)