(19)

(11)

EP 0 528 973 A1

(12)

(43) Date of publication: 03.03.1993 Bulletin 1993/09 (21) Application number: 91910592.0 (22) Date of filing: 29.04.1991

(51) International Patent Classification (IPC):  E04C 3/ 06( . ) E04C 3/ 04( . ) E04C 3/ 07( . ) (86) International application number: PCT/US1991/002944 (87) International publication number: WO 1991/017328 (14.11.1991 Gazette 1991/26)

(84) Designated Contracting States: AT BE CH DE DK ES FR GB GR IT LI LU NL SE (30) Priority: 03.05.1990 US 19900518554 22.03.1991 US 19910674549 (60) Divisional application: 94203383.8 / 0649949 (71) Applicant: Navon, Ram Los Angeles, CA 90046 (US)	(72) Inventor: Navon, Ram Los Angeles, CA 90046 (US) (74) Representative: Weydert, Robert  Office Dennemeyer & Associates S.à.r.l. 55, rue des Bruyères L-1274 Howald L-1274 Howald (LU)