(19)

(11)

EP 0 256 029 A1

(12)

(43) Date of publication: 24.02.1988 Bulletin 1988/08 (21) Application number: 87900211.0 (22) Date of filing: 17.12.1986

(51) International Patent Classification (IPC):  G09B 23/ 18( . ) (86) International application number: PCT/GB1986/000771 (87) International publication number: WO 1987/003991 (02.07.1987 Gazette 1987/14)

(84) Designated Contracting States: AT BE CH DE FR GB IT LI LU NL SE (30) Priority: 17.12.1985 GB 19850030977 (71) Applicant: TRAVIS, Adrian R. L. South Devon TQ10 9HH (GB)	(72) Inventor: TRAVIS, Adrian R. L. South Devon TQ10 9HH (GB)